SDN Review Session Logs 1, 2, 3, & 4

[BloodySurgeon]

04[21:58] <@BloodySurgeon> I will first explain how I will conduct the session
[21:58] <jim> i'm only watching not participating
03[21:58] * BloodySurgeon sets mode: +m
03[21:58] * BloodySurgeon sets mode: -m
04[21:58] <@BloodySurgeon> > then I will explain what I will go over
04[21:58] <@BloodySurgeon> > then I will begin
04[21:59] <@BloodySurgeon> > i will start going through some basic reviews
04[21:59] <@BloodySurgeon> > going through the topics from beginning to end
04[21:59] <@BloodySurgeon> > sometimes I will stop and try to connect different concepts
04[21:59] <@BloodySurgeon> > and other times I may ask a question
04[21:59] <@BloodySurgeon> > I will start by directing the questions to everyone
04[22:00] <@BloodySurgeon> > by I may decide later to direct the questions to individuals
04[22:00] <@BloodySurgeon> > such as: de_la_soul can you tell me what is the difference between a and b
04[22:01] <@BloodySurgeon> > Does everyone understand?
[22:01] <de_la_soul> yep
[22:01] <ezprey> yes
04[22:01] <@BloodySurgeon> > If you do not feel comfortable answering the questions
04[22:01] <@BloodySurgeon> > you may either pass or ask me now to not participate at all
[22:02] <jim> yep
04[22:02] <@BloodySurgeon> > ok. I will start today's lesson with digestion
04[22:02] <@BloodySurgeon> > I want you to first imagine that you just ate a delicious meal filled with proteins, fats, and sugar
04[22:03] <@BloodySurgeon> > as it enters your body from the oral cavity
[22:03] <jim> hahahhaa
[22:03] <jim> lol
04[22:03] <@BloodySurgeon> > your mouth produces salivary amylase also know as ptyalin
04[22:03] <@BloodySurgeon> > to digest the sugars
04[22:04] <@BloodySurgeon> > it will enter your esophagus
04[22:04] <@BloodySurgeon> > and your body has a defense mechanism to not allow these foods to enter your airway
04[22:05] <@BloodySurgeon> > A particular flaplike body
04[22:05] <@BloodySurgeon> > does anyone know the name of this part?
[22:05] <jim> epiglottis
04[22:05] <@BloodySurgeon> > correct
[22:05] <jim> I PWN THIS CHAT
[22:05] <jim> yo!
04[22:05] <@BloodySurgeon> > the epiglottis will prevent the food from entering your airway through th trachea
[22:06] <ezprey> are we allowed to ask questions while you're doing this?
04[22:06] <@BloodySurgeon> > your esophagus will use smooth muscles to squeeze the food down the line
04[22:06] <@BloodySurgeon> > Sure.
04[22:06] <@BloodySurgeon> > if it is relevant
04[22:06] <@BloodySurgeon> > Just say "Question" first
[22:06] <ezprey> okay, I don't have one right now, just asking
04[22:06] <@BloodySurgeon> > ok.
04[22:07] <@BloodySurgeon> > now the first valve that the food enters to the stomach is the lower esophageal sphincter
04[22:07] <@BloodySurgeon> > inside the stomach there are two types of glands
04[22:08] <@BloodySurgeon> > the gastric glands and the pyloric glands
04[22:08] <@BloodySurgeon> > the gastric glands are glands that responds to things in the environment
03[22:08] * Neuronix ([email protected]) has joined #mcat
03[22:08] * ChanServ sets mode: +o Neuronix
04[22:08] <@BloodySurgeon> > when you ordered the delicious meal
04[22:09] <@BloodySurgeon> > your body prepared itself for the incoming nutrition
04[22:09] <@BloodySurgeon> > the gastric glands are divided into three cells
04[22:09] <@BloodySurgeon> > the mucous cells
04[22:09] <@BloodySurgeon> > the chief cells
03[22:09] * KiwiBruin ([email protected]) has joined #mcat
03[22:09] * scalpel ([email protected]) has joined #mcat
[22:09] <KiwiBruin> hihi
04[22:09] <@BloodySurgeon> > and the parietal cells
04[22:10] <@BloodySurgeon> > as you would expect the mucous cells produce mucus
04[22:10] <@BloodySurgeon> > Can anyone explain why mucus is important in the stomach?
[22:10] <ezprey> to protect it from HCl
[22:10] <jim> it keeps the acid from destroying the layers
04[22:10] <@BloodySurgeon> > correct
[22:10] <ezprey> owned
[22:10] <ezprey> !
[22:10] <jim> DAMN U EZPREY!!!
[22:10] <jim> YOU WILL PAY
[22:10] <jim> sorry BS, i'll calm down
04[22:10] <@BloodySurgeon> > now the chief cells produces pepsinogen
04[22:11] <@BloodySurgeon> > that is a zymogen
04[22:11] <@BloodySurgeon> > anything that has an ending of -ogen
04[22:11] <@BloodySurgeon> > is a zymogen
[22:12] <jim> converts to pepsin
04[22:12] <@BloodySurgeon> > BlueElmo, what is a zymogen and why is it important for pepsinogen to be one
[22:12] <ezprey> he might not be here!
04[22:12] <@BloodySurgeon> > ok.
04[22:12] <@BloodySurgeon> > well the answer is obvious
[22:12] <jim> Pepsin is stored as pepsinogen so it will only be released when needed, and does not digest the body's own proteins in the stomach's lining.
04[22:12] <@BloodySurgeon> > it is the inactive form of pepsin
04[22:12] <@BloodySurgeon> > correct
[22:13] <jim> PWNED
04[22:13] <@BloodySurgeon> > now the parietal cells produce HCL
[22:13] <ezprey> he didn't direct the question at you
04[22:13] <@BloodySurgeon> > to lower the pH of the stomach
06[22:13] * jim sits down
04[22:13] <@BloodySurgeon> > making the environment acidic
03[22:13] * jim is now known as gunner
04[22:13] <@BloodySurgeon> > now there is also a feedback system for HCl
03[22:13] * gunner is now known as jimgunner
04[22:14] <@BloodySurgeon> > the pyloric glands
03[22:14] * ksmi117 ([email protected]) has joined #mcat
03[22:14] * ksmi117 ([email protected]) has left #mcat
04[22:14] <@BloodySurgeon> > the pyloric glands consist of G-cells
03[22:14] * BlueElmo ([email protected]) Quit (Client exited)
04[22:14] <@BloodySurgeon> > G-cells produce gastrin
04[22:14] <@BloodySurgeon> > that contracts the stomach and produce more HCl
04[22:15] <@BloodySurgeon> > the food is turned
04[22:15] <@BloodySurgeon> > and molded into a ball of "chyme"
04[22:15] <@BloodySurgeon> > it then enters the small intestine
04[22:15] <@BloodySurgeon> > Question to KiwiBruin
04[22:15] <@BloodySurgeon> > True or False: the duodenum is the major site of absorption
04[22:16] <@BloodySurgeon> > ok i will now move this question to the rest of the class
[22:16] <jimgunner> true!
04[22:16] <@BloodySurgeon> > false
[22:16] <KiwiBruin> sorry
04[22:16] <@BloodySurgeon> > it is the site of digestion
[22:16] <KiwiBruin> lag spike...
[22:16] <ezprey> haha
[22:16] <jimgunner> i am not worthy
04[22:16] <@BloodySurgeon> the ileum and jejunum is the major site of absorption
[22:16] <jimgunner> i am finished
03[22:17] * jimgunner is now known as jimsuicide
04[22:17] <@BloodySurgeon> > the chyme enters the duodenum through the pyloric sphincter
04[22:17] <@BloodySurgeon> > the enzymes in the stomach are most active at a pH near 2
04[22:18] <@BloodySurgeon> > however the enzymes in the small intestine works best at a pH much higher
04[22:18] <@BloodySurgeon> > therefore a base needs to be added
04[22:18] <@BloodySurgeon> > HCO3-
04[22:18] <@BloodySurgeon> > But where does it come from?
[22:19] <de_la_soul> pancreas?
[22:19] <ezprey> pancreas?
04[22:19] <@BloodySurgeon> > The pancreas is filled with lots of enzymes to help out with the digestion
04[22:19] <@BloodySurgeon> > Trypsinogen
04[22:19] <@BloodySurgeon> > chymotrysinogen
04[22:19] <@BloodySurgeon> > pancreatic amylase
03[22:19] * jimsuicide ([email protected]) has left #mcat
04[22:19] <@BloodySurgeon> > lipase
04[22:19] <@BloodySurgeon> > whatever you need to digest, the pancrease has it
04[22:19] <@BloodySurgeon> > that is why the duodenum has the major site of digestion
04[22:20] <@BloodySurgeon> > because the pancrease is close by to help
04[22:20] <@BloodySurgeon> > just below it
04[22:20] <@BloodySurgeon> > Question: Is the small intestine the first site for sugar digestion?
[22:21] <de_la_soul> no
04[22:21] <@BloodySurgeon> > correct, the mouth is
04[22:21] <@BloodySurgeon> > although the pancreas has a lot to offer
04[22:21] <@BloodySurgeon> > the dudenum produces many enzymes of its own
04[22:22] <@BloodySurgeon> > to name a few: maltase, lactase, sucrase
04[22:22] <@BloodySurgeon> > peptidase
04[22:22] <@BloodySurgeon> > yet how do the duodenum communicate with the pancreas?
[22:22] <ezprey> pancreatic duct?
04[22:22] <@BloodySurgeon> > if the duodenum is acidic, how does the pancreas know?
[22:23] <de_la_soul> exocrine glands
04[22:23] <@BloodySurgeon> > the duodenum produces secritin at low pH
04[22:23] <@BloodySurgeon> > secritin stimulates pancrease to release HCO3- along with other things
04[22:23] <@BloodySurgeon> > and as de la soul pointed out
04[22:24] <@BloodySurgeon> > the exocrine hormones go through the pancreatic duct
[22:24] <scalpel> that's not exocrine
04[22:24] <@BloodySurgeon> > what is the difference between exocrine and endocrine hormones?
[22:24] <scalpel> it's enteroendocrine
[22:24] <scalpel> oh wait
[22:24] <scalpel> sorry keep on going
[22:24] <de_la_soul> exocrine goes through blood stream
[22:24] <de_la_soul> endocrine through ducts
04[22:24] <@BloodySurgeon> > :_
[22:25] <scalpel>
04[22:25] <@BloodySurgeon> > I think you have them reversed
[22:25] <de_la_soul> me?
[22:25] <de_la_soul> oh
[22:25] <de_la_soul> oops
04[22:25] <@BloodySurgeon> > endocrine hormones go through the blood
04[22:25] <@BloodySurgeon> > and exocrine goes through the ducts
[22:25] <de_la_soul> ok
04[22:25] <@BloodySurgeon> > Now duodenum also releases CCK
04[22:25] <@BloodySurgeon> > does anyone know what this is?
04[22:26] <@BloodySurgeon> > Cholecystokinin
04[22:26] <@BloodySurgeon> > It does several things
[22:26] <scalpel> biliary gland constriction
04[22:26] <@BloodySurgeon> > yes
[22:26] <scalpel> peristalsis down the bile duct?
04[22:26] <@BloodySurgeon> > correct
04[22:26] <@BloodySurgeon> > and also slows down motility of the food in the small intestine
04[22:27] <@BloodySurgeon> > why is this important?
[22:27] <de_la_soul> for greater absorption
[22:27] <de_la_soul> i think
04[22:27] <@BloodySurgeon> > correct
04[22:27] <@BloodySurgeon> > and digestion
04[22:27] <@BloodySurgeon> > give the body enough time to digest all the lipids before it goes to the rest of the small intestine
04[22:27] <@BloodySurgeon> > true or false: the gall bladder produces the bile
[22:28] <de_la_soul> false
[22:28] <de_la_soul> liver
04[22:28] <@BloodySurgeon> > correct the liver does
[22:28] <@Neuronix> favorite pimp question for when you get to med school
[22:28] <@Neuronix> what's the venous drainage of the gall bladder?
[22:28] <scalpel> hepatic vein
[22:28] <@Neuronix> further down from that
[22:28] <scalpel> central vein
[22:28] <@Neuronix> ?!?!
[22:28] <@Neuronix> further towards the gall bladder
[22:29] <scalpel> portal vein drains into the liver
[22:29] <scalpel> oh gall bladder
[22:29] <scalpel> misread the question
04[22:29] <@BloodySurgeon> > *cough*
[22:29] <@Neuronix> I know scalp
04[22:29] <@BloodySurgeon> > do I have to DeVoice someone/
[22:29] <@Neuronix> You didn't set +m first
03[22:29] * BloodySurgeon sets mode: +m
04[22:29] <@BloodySurgeon> >
04[22:30] <@BloodySurgeon> > ok.
[22:30] <@Neuronix> The answer is it's a trick question, there is no cystic vein as there as a cystic artery (gall bladder artery is the cystic artery)
[22:30] <@Neuronix> and it's just minor veins of the liver
[22:30] <@Neuronix> ok continue BS
04[22:30] <@BloodySurgeon> > now the liver is a very important organ
[22:30] <@Neuronix> When you get to third year you will thank me!
04[22:30] <@BloodySurgeon> > it can does much more than make bile
04[22:30] <@BloodySurgeon> > *do
04[22:30] <@BloodySurgeon> > it is the site for gluconeogenesis, glycogenolysis, glycogenesis
04[22:31] <@BloodySurgeon> > cholesterol, lipogenesis
04[22:31] <@BloodySurgeon> > urea cycle
04[22:31] <@BloodySurgeon> > coagulation factors
04[22:31] <@BloodySurgeon> > and an important topic i will discuss later
04[22:31] <@BloodySurgeon> > angiotensionogen
04[22:31] <@BloodySurgeon> (forgive my spellings if I have typos)
04[22:32] <@BloodySurgeon> biology has tough words
04[22:32] <@BloodySurgeon> What is the urea cycle?
04[22:32] <@BloodySurgeon> and where does it get its reactants from
05[22:32] -de_la_soul- gets rid of nitrogen
04[22:33] <@BloodySurgeon> correct
04[22:33] <@BloodySurgeon> but what does it make
04[22:33] <@BloodySurgeon> and where is the nitrogen from?
05[22:33] -de_la_soul- nitrogen from peptides...it makes urea
04[22:33] <@BloodySurgeon> correct
03[22:34] * Neuronix sets mode: -m
04[22:34] <@BloodySurgeon> say if you are not getting any peptides from the enviornment
04[22:34] <@BloodySurgeon> where is the nitrogen produced?
04[22:34] <@BloodySurgeon> its a bs question, but a question that can arise
04[22:34] <@BloodySurgeon> translation
[22:35] <de_la_soul> oh
04[22:35] <@BloodySurgeon> ok we can move on now
[22:35] <de_la_soul> heh trick q
04[22:35] <@BloodySurgeon> we left off with duodenum in the small intestine
04[22:35] <@BloodySurgeon> duodenum leads to jejunum
04[22:35] <@BloodySurgeon> then to ileum
04[22:35] <@BloodySurgeon> jejunum and ileum are the major site for absorption
04[22:36] <@BloodySurgeon> how do they absorp nutrients such as sugar?
04[22:36] <@BloodySurgeon> *absorb
[22:36] <de_la_soul> microvilli
04[22:36] <@BloodySurgeon> correct
04[22:37] <@BloodySurgeon> now we get into the large intestine
04[22:37] <@BloodySurgeon> what part of the large intestine does the ileum lead into
[22:37] <de_la_soul> not sure
[22:37] <de_la_soul> cecum?
04[22:37] <@BloodySurgeon> correct
04[22:38] <@BloodySurgeon> now from the cecum you can enter the colon or into the appendix
04[22:38] <@BloodySurgeon> the colon is divided into three parts
04[22:38] <@BloodySurgeon> the ascending colon
04[22:38] <@BloodySurgeon> the transverse colon
04[22:38] <@BloodySurgeon> the descending colon
04[22:38] <@BloodySurgeon> what is the major function of the large intestine
[22:38] <de_la_soul> absorb water, I think
04[22:39] <@BloodySurgeon> correct
04[22:39] <@BloodySurgeon> with
04[22:39] <@BloodySurgeon> water rarely goes alone
04[22:39] <@BloodySurgeon> what likes to accompany it
[22:39] <KiwiBruin> electrolytes?
04[22:39] <@BloodySurgeon> correct
04[22:39] <@BloodySurgeon> so hypothetically what will happen if the large intestine does not do its job
[22:40] <de_la_soul> umm
[22:40] <de_la_soul> blood pressure will drop
04[22:40] <@BloodySurgeon> think medically
04[22:40] <@BloodySurgeon> as a symptom
04[22:40] <@BloodySurgeon> you will get watery stool
[22:40] <de_la_soul> hypotension?
04[22:40] <@BloodySurgeon> what is watery stool?
[22:41] <KiwiBruin> diarrhea
04[22:41] <@BloodySurgeon> correct
04[22:41] <@BloodySurgeon> now lets look at the nephron
04[22:41] <@BloodySurgeon> the nephron can be divided into the corect
04[22:41] <@BloodySurgeon> *cortex
04[22:41] <@BloodySurgeon> or the upper and lower medulla
04[22:42] <@BloodySurgeon> for our purposes I will use medulla to refer to both
04[22:42] <@BloodySurgeon> upper and lower
04[22:43] <@BloodySurgeon> nutrients enter the nephron through the bowman's capsule
04[22:44] <@BloodySurgeon> from the afferant arteriole to the glomerulus to the bowman's capsule
04[22:44] <@BloodySurgeon> the capsule has a selective filter that does now allow large particles to enter through it
04[22:44] <@BloodySurgeon> the higher the blood pressure the more is filtrated inside
04[22:44] <@BloodySurgeon> the particles that are not filter leave through the efferent arteriole
04[22:45] <@BloodySurgeon> Question: what is albumin?
[22:45] <de_la_soul> carries proteins
[22:45] <de_la_soul> in the blood
[22:46] <de_la_soul> well it is a protein
04[22:46] <@BloodySurgeon> correct
[22:46] <de_la_soul> it transports something in the bloodstream :\
04[22:46] <@BloodySurgeon> does it enter the nephron?
[22:46] <de_la_soul> no
[22:46] <de_la_soul> too big
04[22:46] <@BloodySurgeon> what would happen if it did?
[22:46] <de_la_soul> get stuck somewhere?
04[22:46] <@BloodySurgeon> think of where it is located
[22:46] <de_la_soul> or clog it up
04[22:46] <@BloodySurgeon> think logically
04[22:47] <@BloodySurgeon> something big goes through a small opening
04[22:47] <@BloodySurgeon> what happens when it passes it
[22:47] <de_la_soul> ruptures
04[22:47] <@BloodySurgeon> close
[22:47] <de_la_soul> I dunno
04[22:47] <@BloodySurgeon> it tears larger openings
[22:47] <KiwiBruin> tears holes?
04[22:47] <@BloodySurgeon> consequently
04[22:47] <@BloodySurgeon> you will urinate blood
04[22:48] <@BloodySurgeon> now the pathways of the nephron are as follows
04[22:49] <@BloodySurgeon> proximal convuluted tubule --> descending convoluted tubule --> Loop of Henle --> Ascending convoluted tubule --> Distal convoluted tubule --> collecting duct
04[22:50] <@BloodySurgeon> ions that are important will be reabsorb back into the bloodstream if it is needed
04[22:50] <@BloodySurgeon> in the proximal tubule, sodium, chloride, water, aa, glucose, and Ca++ are sent back
04[22:51] <@BloodySurgeon> all are actively transported except for Cl- and water
04[22:51] <@BloodySurgeon> which are passively diffused
04[22:51] <@BloodySurgeon> It is very important that Ca++ is sent back
03[22:51] * scalpel ([email protected]) has left #mcat
04[22:52] <@BloodySurgeon> Where do you think the Ca++ come from
[22:52] <KiwiBruin> bones?
04[22:52] <@BloodySurgeon> correct
04[22:53] <@BloodySurgeon> bones are made from a complex of calcium and phosphate
04[22:53] <@BloodySurgeon> when PTH is released
04[22:53] <@BloodySurgeon> the calcium and phosphate is released into the bloodstream
04[22:54] <@BloodySurgeon> so why do you think the nephron reabsorbs Ca++ but not phosphate?
[22:54] <de_la_soul> maybe phosphate is more widely available
[22:54] <de_la_soul> from atp -> adp
04[22:55] <@BloodySurgeon> think of it like this
04[22:55] <@BloodySurgeon> why does the nephron want to seperate the too?
04[22:55] <@BloodySurgeon> why did the body produce PTH to begin with
04[22:55] <@BloodySurgeon> *two
[22:56] <de_la_soul> well to break down bone
04[22:56] <@BloodySurgeon> if the phosphate was sent back into the bloodstream then it will just complex back with ca++ and rebuild the bones
[22:56] <de_la_soul> oh i see
04[22:56] <@BloodySurgeon> the body is excreting the phosphate so it can use the ca++ for other means
[22:56] <KiwiBruin> Do we have to know what the other means are?
04[22:56] <@BloodySurgeon> yes
04[22:56] <@BloodySurgeon> where do we use ca++?
04[22:57] <@BloodySurgeon> (oh and dont be frighten if you dont know everything I ask)
04[22:57] <@BloodySurgeon> I am just trying to be as thorough as possible
04[22:57] <@BloodySurgeon> because it looks like you guys know your stuff
[22:57] <de_la_soul> i don't remember
[22:57] <de_la_soul> been a while since i studied this stuff
04[22:57] <@BloodySurgeon> I will help
04[22:58] <@BloodySurgeon> does neurons ring a bell?
[22:58] <de_la_soul> yeah
[22:58] <de_la_soul> sarcoplasm reticulum
04[22:58] <@BloodySurgeon> correct
04[22:59] <@BloodySurgeon> that is usually the reason why the body produces PTH
04[22:59] <@BloodySurgeon> (we wont have enough time to go through the endocrine system, but I will finish off the nephron)
04[22:59] <@BloodySurgeon> now at the descending convoluted tubule water is passive diffused
04[23:00] <@BloodySurgeon> does Na+Cl- follow?
[23:00] <de_la_soul> yes
04[23:00] <@BloodySurgeon> no
04[23:00] <@BloodySurgeon> the tubule does not allow it to diffuse at this location
04[23:01] <@BloodySurgeon> however at the ascending tubule it does
[23:01] <ezprey> it's only permeable to water
04[23:01] <@BloodySurgeon> correct
04[23:02] <@BloodySurgeon> now here is a question, which is simple if you memorized but diffucult to figure out
04[23:02] <@BloodySurgeon> why is the ascending tubule thick at the cortex but thin in the medulla
[23:03] <de_la_soul> thicker so passive diffusion can't occur?
[23:03] <KiwiBruin> thicker walls for active pumping of Na+?
04[23:03] <@BloodySurgeon> correct
[23:03] <ezprey> which one's corect?
04[23:03] <@BloodySurgeon> I dont have time to get into this
04[23:03] <@BloodySurgeon> kiwibruin
[23:03] <ezprey> why can't thin walls pump Na+?
04[23:04] <@BloodySurgeon> I dont have time to answer this
04[23:04] <@BloodySurgeon> but I will give you a site at the ense
04[23:04] <@BloodySurgeon> end
04[23:04] <@BloodySurgeon> now at the distal convoluted tuble
04[23:05] <@BloodySurgeon> Na+ is actively transported out and H+, K+ is actively transported in
04[23:05] <@BloodySurgeon> True or false: ADH allows Na+ AND H2O to leave the nephron
[23:06] <ezprey> true
[23:06] <ezprey> "always digging holes"
04[23:06] <@BloodySurgeon> incorrect
[23:06] <ezprey> ah the AND
[23:06] <ezprey> it's just Na+
[23:06] <KiwiBruin> aldosterone
04[23:06] <@BloodySurgeon> aldosterone
04[23:07] <@BloodySurgeon> aldosterone works at the distal tubule for active transport of Na+ and water follows
04[23:07] <@BloodySurgeon> ADH works at the collecting duct
04[23:07] <@BloodySurgeon> and only allows water to leave through aquaporins
04[23:07] <@BloodySurgeon> what is another difference between these two hormones?
[23:08] <KiwiBruin> one is a steriod
04[23:08] <@BloodySurgeon> correct
04[23:08] <@BloodySurgeon> which one?
[23:08] <de_la_soul> aldosterone
04[23:08] <@BloodySurgeon> correct
04[23:08] <@BloodySurgeon> where is it produced?
[23:08] <de_la_soul> adrenal cortex
[23:08] <de_la_soul> maybe
04[23:08] <@BloodySurgeon> correct
[23:08] <KiwiBruin> yes
04[23:09] <@BloodySurgeon> what stimulates the adrenal cortex and what creates aldosterone in the adrenal cortex
03[23:09] * @Neuronix ([email protected]) Quit (Ping timeout: 121 seconds)
04[23:09] <@BloodySurgeon> ACTH
04[23:10] <@BloodySurgeon> from the anterior pituitary
04[23:10] <@BloodySurgeon> think of ACth
04[23:10] <@BloodySurgeon> AC for adrenal cortex
04[23:10] <@BloodySurgeon> adrenocorticotropic hormone
04[23:10] <@BloodySurgeon> spelling could be off
04[23:10] <@BloodySurgeon> where is the adrenal glands located?
[23:10] <ezprey> above kidneys?
04[23:10] <@BloodySurgeon> correct
04[23:11] <@BloodySurgeon> so you know it should affect the kidneys
04[23:11] <@BloodySurgeon> it produces glucocorticoids
04[23:11] <@BloodySurgeon> mineral coricoids
04[23:11] <@BloodySurgeon> and sex hormones
[23:11] <KiwiBruin> not sure.
04[23:11] <@BloodySurgeon> what is an example of mineral and glucocorticoids
[23:11] <ezprey> cortisol
04[23:12] <@BloodySurgeon> and for glucocorticoids?
04[23:12] <@BloodySurgeon> sorry
04[23:12] <@BloodySurgeon> thats for glucocorticoids
04[23:12] <@BloodySurgeon> now for mineral corticoids
04[23:12] <@BloodySurgeon> aldosterone!
04[23:13] <@BloodySurgeon> last note then I will have to end the session
04[23:13] <@BloodySurgeon> every gland will only produce one type of hormone
04[23:13] <@BloodySurgeon> the pituitary will only produce peptide hormones
04[23:13] <@BloodySurgeon> andrenal coretex --> steroid
04[23:14] <@BloodySurgeon> andrenal medulla --> thyrosine
04[23:14] <@BloodySurgeon> Ok now this will conclude my review session

---

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[hellothere00]

that was really helpful, thanks! I re-took notes after reading this

 

[capn jazz]

04[23:14] <@BloodySurgeon> andrenal medulla --> thyrosine

Sorry, was that a typo? thought adrenal medulla produced catecholamines. The thyroid produces thyrosine.

 

[FIREitUP]

Sorry, was that a typo? thought adrenal medulla produced catecholamines. The thyroid produces thyrosine.

catecholamines are tyrosine derivatives, although they don't diffuse through the cell membrane, they have receptors on cell surfaces.
you were thinking of thyroxine, which is secreted by the thyroid gland, which is also a tyrosine derivative.

 

[BloodySurgeon]

<@BloodySurgeon> I will start.
<@BloodySurgeon> Ok, so first I will tell you the overview of our lesson plan
<@BloodySurgeon> and then follow up with the rules and conducts of this lesson
<@BloodySurgeon> and then will begin
<@BloodySurgeon> Today's topic, as requested, will be Electricity and magnetism
<@BloodySurgeon> we will go over circuits, capacitors, resistors, electric fields, magnetic fields and forces
<@BloodySurgeon> I will be asking questions throughout the lesson that could either be directed to a certain individual
<@BloodySurgeon> or to the whole class
<@BloodySurgeon> If it is to an individual, I will mention that persons name
<@BloodySurgeon> such as, KiwiBruin, can you tell me the formula for a magnetic force?
<@BloodySurgeon> you can either request to not answer by either stating "pass"
<@BloodySurgeon> or tell me now that you do not wish to participate
<KiwiBruin> oh okay
<@BloodySurgeon> please be civil and allow others to answer.
<daffodilh> i'm just observing
<Flapjacks> are you asking KB or was that just hypothetical
<@BloodySurgeon> If you have any questions, you may ask me privatly or publicly and i will try to integrate it into the lesson
<@BloodySurgeon> hypothetical
<@BloodySurgeon> now let us begin.
<@BloodySurgeon> it is an important aspect in the mcat to know all the main physic equations
<@BloodySurgeon> however it is even more important to understand them
<@BloodySurgeon> and why it is written the way it is
<@BloodySurgeon> i am going to state the relevent formulas that i will discuss today
<@BloodySurgeon> there are more than these, but that is going to be your resposibily to go over them
<@BloodySurgeon> if you have any question on any of the variables let me know
<@BloodySurgeon> however, this is just the basics
<@BloodySurgeon> Q = CV, V =IR, I = Q / t, P = IV, P = work/time, C = k(epsilon)A/d, R= pL/A
<@BloodySurgeon> use these as refrences when I will discuss some of these topics
<@BloodySurgeon> I will repeat some of them as well
<@BloodySurgeon> let us first look at an example of a circuit
<@BloodySurgeon> http://www.tpub.com/neets/book1/chapter3/32NE0098.GIF
<@BloodySurgeon> follow this link as I will be talking about it
<Chocolatebear89> okay
<@BloodySurgeon> Figure 1A is the overall diagram of a basic circuit of a baterry and a resistor
<@BloodySurgeon> R1 and R2 are in parallel to R3
<@BloodySurgeon> there is a quick and fast way to solving the Req in 3 seconds without any real mathematics
<@BloodySurgeon> we know that resistors add in series
<@BloodySurgeon> and for parallel: 1/r + 1/r = 1/req
<@BloodySurgeon> therefore
<@BloodySurgeon> R1 + R2 = 400
<@BloodySurgeon> now since 400 is parallel to R3 which is also 400
<@BloodySurgeon> a quick way to deduce this is
<@BloodySurgeon> whenever two resistors are in parallel and equal each other
<@BloodySurgeon> the sum is just half of one of them
<@BloodySurgeon> which is shown in Figure 1C
<@BloodySurgeon> where two resistors of 400 ohms in parallel is 200 ohm
<@BloodySurgeon> and then in series with a 1.2kohm is 1.2 ohms
<@BloodySurgeon> which is shown in figure 1D
<@BloodySurgeon> Now, we know the equation for circuits is V = IR
<@BloodySurgeon> what will the overall current be in this diagram?
<@BloodySurgeon> V = 300 volts
<KiwiBruin> 300/1200 = .25A
<@BloodySurgeon> eactly
<@BloodySurgeon> or we can think of it as 3/12 = 1/4
<@BloodySurgeon> now lets go to figure 1b
<@BloodySurgeon> and replace Req 1 to 200 ohms
<@BloodySurgeon> Which resistor will get more current? the Req1 or Req 2?
<ezprey> Req1
<@BloodySurgeon> V = IR, therefore if the resistor is decreased by 1/2 the current will increase by 2
<KiwiBruin> I agree =]
<@BloodySurgeon> easy enough
<@BloodySurgeon> Now how would the calculations for a capacitor in series and parallel be different than a resistor?
<Chocolatebear89> flipped
<@BloodySurgeon> yes, for a capacitor, capacitors in series add and parallel add the reciporcals
<@BloodySurgeon> a way to remember this is to look at its formula
<@BloodySurgeon> R = p L / A
<@BloodySurgeon> when the length of the resistors increase
<@BloodySurgeon> more resistors in a long wire
<@BloodySurgeon> then the resistance increase
<@BloodySurgeon> if the area increase, more resistors in parallel
<@BloodySurgeon> the resistance decrease
<@BloodySurgeon> C = k (epsilon) A / d
<Chocolatebear89> oh
<@BloodySurgeon> which is pretty much the recipical
<Chocolatebear89> that's coool
<@BloodySurgeon> since we found the Req, I, and voltage
<@BloodySurgeon> we can find the individual current and voltage through each resistor
<@BloodySurgeon> to help with this problem we will have to look at kirchoff's laws
<@BloodySurgeon> there are two important rules
<@BloodySurgeon> whatever current enters an intersection an equal current leaves it
<@BloodySurgeon> http://upload.wikimedia.org/wikipedia/commons/6/69/KCL.png
<@BloodySurgeon> looking at this diagram
<@BloodySurgeon> we can see that i2 + i3 = i1 + i4
<@BloodySurgeon> given: i1 = 1A, i2= 2A, i3=3A, and i4= 4A
<@BloodySurgeon> kiwibruin this next question is for you
<BS> if I add another wire to the intersection
<BS> what is the current exiting it?
<cathyrn887> what was the last website we had to go to?
<BS> http://upload.wikimedia.org/wikipedia/commons/6/69/KCL.png
<cathyrn887> thank you
* BS is now known as bloodysurgeon
<KiwiBruin> i2+i3?
<Chocolatebear89> -i1-i4
<bloodysurgeon> the current will be zero
<bloodysurgeon> since i1 + i4 already equals i2 + i3
<bloodysurgeon> now lets look at a capacitor
<cathyrn887> sorry i completely missed all that could you please go over it again
<bloodysurgeon> ok sure
<bloodysurgeon> let me restate what i said before
<bloodysurgeon> you may have missed it because of the other guy
<bloodysurgeon> <@BloodySurgeon> given: i1 = 1A, i2= 2A, i3=3A, and i4= 4A
<KiwiBruin> sounds great
<bloodysurgeon> kirchoff's rule states that the current entering an intersection is equal to what leaves it
<bloodysurgeon> therefore since, i1 + i4 = 5A
<bloodysurgeon> and i3 + i2 = 5A
<bloodysurgeon> if we were to add another wire to the intersection
<bloodysurgeon> the current must equal 0 A
<bloodysurgeon> now let us look at a capacitor
<cathyrn887> why?
<Chocolatebear89> yeah why, doesn't it split
<Chocolatebear89> so i1 and i4 and i-new has total of 5A
<bloodysurgeon> im sorry I should have been more clear
* Bones ([email protected]) has joined #mcat
<bloodysurgeon> I cant draw so please be patient
<bloodysurgeon> please imagine a wire added to the intersection i gave you
<bloodysurgeon> and now i am telling you the set current in each one
<bloodysurgeon> however the current in the unknown wire is a mystery
<bloodysurgeon> pretend the wire was always there
<bloodysurgeon> NOW, if i1 = 1A, i2 = 2A, etc
<bloodysurgeon> what will the new i5 = ?
<Chocolatebear89> oh ok
<bloodysurgeon> if i1 + i4 +i5 = i2 + i3
<cathyrn887> zero coz current in = current out
<bloodysurgeon> exactly
<Chlorina> good job cathyrn887
<bloodysurgeon> now let us look at a capacitor
<bloodysurgeon> http://www.tpub.com/neets/book10/NTX1-25.GIF
04[20:38] <bloodysurgeon> notice to the left the battery has a plus and a minus
<bloodysurgeon> and the plates have a plus and a minus
<bloodysurgeon> we know that the electric field is form between these parallel plates
<bloodysurgeon> always from positive to negative
<Chlorina> bloody surgeon
<bloodysurgeon> FlapJack, if I were to shoot a beta particle from left to right through this field, which direction will the particle deflect to
<bloodysurgeon> yes.
<Chlorina> ive been writing my work down on my e-tablet
<Chlorina> can you check it for me for erros?
<Chlorina> errors
<Flapjacks> left
<bloodysurgeon> after this is done
<Flapjacks> wait
<Flapjacks> right
<Chlorina> it will only take a second to check
<Chlorina> i dont want to be doing it wrong
<KiwiBruin> question... what charge does a beta particle have?
<bloodysurgeon> a beta particle is like an election
<Flapjacks> beta negative
<cathyrn887> neg
<Flapjacks> so it goes to the right
<KiwiBruin> oh okay
<KiwiBruin> cool
<Flapjacks> oh np
<Flapjacks> to the left
<KiwiBruin> i thoguht there was a beta positive too?
<Chlorina> flapjacks
<KiwiBruin> maybe not.
<bloodysurgeon> an electron force will be up
<Chlorina> thanks for showing me this super cool site
<Flapjacks> alpha positive
<bloodysurgeon> always opposite to the electric field
<Flapjacks> ya
<Flapjacks> towards positive charge
<bloodysurgeon> and since there is a velocity from left to right
<bloodysurgeon> you will see a trajectory leaning upwards
<bloodysurgeon> similar to an object in flight
<bloodysurgeon> cathyrn, which direction will a gamma particle deflect to
<cathyrn887> it won't deflect
<bloodysurgeon> correct
<cathyrn887> no charge
<bloodysurgeon> Now a harder problem
<bloodysurgeon> phosej...
<bloodysurgeon> if i added a dipolar molecule with a positive and negatice end with an angle of 45 degrees to the horizon
<bloodysurgeon> will there be translation motion?
<Bones> no
<bloodysurgeon> correct
<cathyrn887> explain
<bloodysurgeon> how about rotational motion
<bloodysurgeon> I will
<KiwiBruin> yes~
<Bones> there'll be a rotational moment
<@bloodysurgeon> now look at it this way
<@bloodysurgeon> the positive portion of a molecule will be attracted to the negative plate
<Bones> you know define the dipolar molecule
<@bloodysurgeon> whereas the negative portion will be attracted to the positve plate
<Bones> is the centre of mass in the middle?
<@bloodysurgeon> yes.
<@bloodysurgeon> mass does not matter
<cathyrn887> tehn why is there rotationa;
<@bloodysurgeon> F = qE
<Bones> *nod*
<@bloodysurgeon> since it is at a 45 degree angle to the horrizon one side will have a force pointing down and one end have a force pointing up
<@bloodysurgeon> the have torque
<@bloodysurgeon> *they
<@bloodysurgeon> but no motion since qE = -qE
<@bloodysurgeon> F(positive charge) = F(negative charge)
<@bloodysurgeon> now we know capacitors store energy
<@bloodysurgeon> PE = 1/2 QV
<@bloodysurgeon> what is the difference between a battery and capacitor?
<Flapjacks> battery stores charge and capacitor seperates?
<@bloodysurgeon> let me give a hint of what i am talking about
<KiwiBruin> capacitor becomes a battery if u sharge it
<KiwiBruin> and cut it off?
<@bloodysurgeon> what is the differnce in how they dissapate the energy
<@bloodysurgeon> yes.
<Flapjacks> battery is constant and capacitor is alternative
<Bones> time factor?
[20:50] <Bones> exponential
04[20:50] <@bloodysurgeon> yes
[20:50] <Bones> yes to whom?
04[20:50] <@bloodysurgeon> a capacitor releases its energy suddenly and quickly
04[20:50] <@bloodysurgeon> while the battery is constant and is smooth
[20:51] <Bones> neat
[20:51] <Bones> maybe you can explain to me stuff about membranes
[20:51] <Bones> membrane potential
04[20:51] <@bloodysurgeon> now how does one make a magnetic field?
[20:51] <Flapjacks> maybe during bio
[20:51] <Bones> cool
[20:51] <Bones> motion of charge
04[20:51] <@bloodysurgeon> yep
[20:51] <Flapjacks> isnt magnetic field caused by the movement of electrtons
04[20:51] <@bloodysurgeon> yes
04[20:52] <@bloodysurgeon> lets look at this diagram for a second
04[20:52] <@bloodysurgeon> http://cr4.globalspec.com/PostImages/200902/001_A767889D-D07E-3934-B157667C322B53AE.JPG
04[20:52] <@bloodysurgeon> the current is going up
04[20:53] <@bloodysurgeon> which way is the electrons flowing?
[20:53] <Chocolatebear89> down
[20:53] <KiwiBruin> UPPPPPPPP
[20:53] <KiwiBruin> wait
[20:53] <Flapjacks> Sideways
[20:53] <KiwiBruin> haha
04[20:53] <@bloodysurgeon> correct down
03[20:53] * Neuronix is now known as bopm
[20:53] <Bones> current is opposite to motion of electrons
04[20:53] <@bloodysurgeon> exactly
04[20:53] <@bloodysurgeon> now there are multiple ways to do the right hand rule
[20:53] <Bones> by definition i believe
03[20:53] * bopm is now known as Neuronix
04[20:53] <@bloodysurgeon> for a wire, this one is easy
[20:53] <KiwiBruin> silly me =D
04[20:53] <@bloodysurgeon> just point your right thumb in the direction of the currect
04[20:54] <@bloodysurgeon> and then curve your hand
04[20:54] <@bloodysurgeon> you will make a magnetic field such as the diagram
04[20:54] <@bloodysurgeon> into the page to the right of the wire
04[20:54] <@bloodysurgeon> and out of the page to the left
[20:54] <Bones> uh huh
04[20:54] <@bloodysurgeon> say we have a second wire that is within the magnetic field of the first wire
04[20:55] <@bloodysurgeon> such as presented in the picture
04[20:55] <@bloodysurgeon> Bones, can you explain what direction is the force and why?
04[20:55] <@bloodysurgeon> the force the second wire has
04[20:55] <@bloodysurgeon> http://scienceblogs.com/startswithabang/upload/2009/04/the_left-hand_rule/Right_hand_rule.png
[20:56] <Bones> mmm
04[20:56] <@bloodysurgeon> F = qvBsin0
[20:56] <Bones> the wires will repell
[20:56] <cathyrn887> to the left
[20:56] <cathyrn887> to the right
[20:56] <KiwiBruin> attract?
04[20:56] <@bloodysurgeon> this means that the force, magnetic field, and velocity will all be perpendicular to each other
[20:56] <cathyrn887> attract
04[20:56] <@bloodysurgeon> using the right hand method
04[20:57] <@bloodysurgeon> on the second wire
04[20:57] <@bloodysurgeon> we notice the currect is up
[20:57] <Bones> but there is a current in the second wire
04[20:57] <@bloodysurgeon> the magnetic field is into the page
04[20:57] <@bloodysurgeon> therefore the force must be left
[20:57] <Bones> oh
04[20:57] <@bloodysurgeon> and the wire will consequently move towards the first wire
[20:57] <cathyrn887> why
04[20:57] <@bloodysurgeon> right hand rule
04[20:57] <@bloodysurgeon> http://www.diracdelta.co.uk/science/source/f/l/flemings right hand rule/image001.jpg
[20:58] <KiwiBruin> A wire doesn't play with its own magnetic field rmr that ^^
[20:58] <Bones> oh yes
[20:58] <Bones> i remember that rule now
[20:58] <Flapjacks> is that your hand?
04[20:58] <@bloodysurgeon> true, but there is a second wire causing a magnetic field on it
04[20:59] <@bloodysurgeon> no that is not my hand, it is also not the way i do my second hand rule
04[20:59] <@bloodysurgeon> but any method would work
[20:59] <KiwiBruin> I got a question...
04[20:59] <@bloodysurgeon> shoot
[21:00] <KiwiBruin> when do we use the first method (the curling one) and when do we use the perpendicular one?
04[21:00] <@bloodysurgeon> the first method is for finding the magnetic field in a wire
04[21:00] <@bloodysurgeon> the second is to find the magnetic FORCE from a moving particle
[21:00] <KiwiBruin> awesome
04[21:00] <@bloodysurgeon> now lets go back to this diagram
04[21:00] <@bloodysurgeon> http://www.tpub.com/neets/book10/NTX1-25.GIF
[21:00] <KiwiBruin> thanks BS!
04[21:01] <@bloodysurgeon> let us say we have a magnetic field into the page
04[21:01] <@bloodysurgeon> which dirrection will the magnetic force be?
04[21:02] <@bloodysurgeon> for a negatice particle
[21:02] <KiwiBruin> left
[21:02] <KiwiBruin> right
[21:02] <Bones> lol
[21:02] <cathyrn887> down
[21:02] <KiwiBruin> i'm gonna be quiet for a bit ^^
04[21:02] <@bloodysurgeon> correct down
04[21:02] <@bloodysurgeon> its moving left to right
04[21:02] <@bloodysurgeon> the magnetic field is into the page
04[21:02] <@bloodysurgeon> and an electron is always opposite of the right hand rule
04[21:02] <@bloodysurgeon> the right hand rule will tell you up
[21:03] <KiwiBruin> how do we know it is moving left to right?
04[21:03] <@bloodysurgeon> but since its a negative particle you will have force pointing down
[21:03] <KiwiBruin> ah okay
04[21:04] <@bloodysurgeon> now if i shoot the same electron from left to right
04[21:04] <@bloodysurgeon> which direction is the electric force?
[21:04] <Flapjacks> down
[21:04] <Flapjacks> and up
[21:04] <Flapjacks> so 0?
04[21:04] <@bloodysurgeon> up
04[21:04] <@bloodysurgeon> not necessarily
04[21:05] <@bloodysurgeon> if the electric force equal the magnetic force
04[21:05] <@bloodysurgeon> then you will have 0
04[21:05] <@bloodysurgeon> scientist use this to manipulate particles
04[21:05] <@bloodysurgeon> such as mass spectroscopy
[21:05] <Chocolatebear89> i seee
[21:06] <KiwiBruin> so if the magnetic force down
[21:06] <KiwiBruin> but the electric force is up?
04[21:06] <@bloodysurgeon> i will explain the overview how it works after i get a few things down with u
[21:06] <KiwiBruin> i mean is not if...
[21:06] <Flapjacks> so force is like current
[21:06] <Flapjacks> if the electrons go up, force is down
04[21:07] <@bloodysurgeon> now chocolatebear, what will be the velecocity of such a particle?
[21:07] <Chocolatebear89> pass
04[21:07] <@bloodysurgeon> no FJ
04[21:07] <@bloodysurgeon> there are two forces acting on the particle
04[21:07] <@bloodysurgeon> electric force pointing up
04[21:07] <@bloodysurgeon> and magnetic force pointing down
04[21:08] <@bloodysurgeon> they can cancel each other out
04[21:08] <@bloodysurgeon> and have no vertical force
04[21:08] <@bloodysurgeon> however, there will still be horizontal force
[21:08] <cathyrn887> e/bsin
[21:09] <Flapjacks> k
04[21:09] <@bloodysurgeon> correct
04[21:09] <@bloodysurgeon> qE + qvB = 0
[21:09] <Chlorina> Flapjacks stop getting things wrong
04[21:09] <@bloodysurgeon> q's cancel out
[21:09] <Chlorina> i need to cheat off you
04[21:09] <@bloodysurgeon> E = vB
04[21:09] <@bloodysurgeon> v = E/B
[21:09] <Flapjacks> lol
04[21:10] <@bloodysurgeon> therefore we can manipule the speed with the electric and magnectic field
04[21:10] <@bloodysurgeon> now how can we relate this to mass?
04[21:10] <@bloodysurgeon> http://wpcontent.answers.com/wikipe...netic.svg/180px-Alphaparticlemagnetic.svg.png
04[21:10] <@bloodysurgeon> go to this new diagram
[21:10] <Flapjacks> because certain masses will only be able to reach the end of the tunnel
04[21:10] <@bloodysurgeon> no.
04[21:11] <@bloodysurgeon> mass has no relavence in the that situation
[21:11] <Flapjacks> i thought you were talking about mass spec
[21:11] <Flapjacks> mah bad
[21:11] <Chocolatebear89> different paths taken
04[21:11] <@bloodysurgeon> in a regular magnetic field
04[21:12] <@bloodysurgeon> an alpha particle (one with a positive charge) will go in a circular path
[21:12] <KiwiBruin> centripetal acceleration? a = mv^2/r
04[21:12] <@bloodysurgeon> exactly
04[21:12] <@bloodysurgeon> we know that the force is qvB
04[21:12] <@bloodysurgeon> and F = ma
04[21:12] <@bloodysurgeon> therefore
04[21:13] <@bloodysurgeon> qvB = mv^2/r
[21:13] <KiwiBruin> whoops* i messed that up... =_=
04[21:13] <@bloodysurgeon> qB = mv/r
04[21:13] <@bloodysurgeon> r=mv/Bq
04[21:14] <@bloodysurgeon> imagine there is a detector 12 feet above the alpha particle
04[21:14] <@bloodysurgeon> and we want to manipulate the magnetic field to hit it
[21:14] <cathyrn887> is that also relevant for electrons
04[21:14] <@bloodysurgeon> yes
04[21:14] <@bloodysurgeon> I will get there too
04[21:15] <@bloodysurgeon> we can determine the mass of the particle by knowing the magnetic field and radius of the particle
04[21:15] <@bloodysurgeon> now how do we know the velocity?
04[21:16] <@bloodysurgeon> from our last situation with a electic field and magnetic field
04[21:16] <@bloodysurgeon> we can manipulate the velocity
04[21:16] <@bloodysurgeon> v = E/B
03[21:16] * Neuronix is now known as BOPM
04[21:16] <@bloodysurgeon> therefore we have everything we need to find the mass of a particle
[21:16] <cathyrn887> is the Egiven
04[21:16] <@bloodysurgeon> yes
04[21:16] <@bloodysurgeon> you are the scientist
04[21:16] <@bloodysurgeon> and can manipulate all the energies you want
[21:17] <cathyrn887> oic
04[21:17] <@bloodysurgeon> however you need to find the mass of the object
04[21:17] <@bloodysurgeon> now how do we change the situation to detect electrons?
04[21:17] <@bloodysurgeon> where will the detector plate be located?
[21:18] <KiwiBruin> so moving left to right
04[21:18] <@bloodysurgeon> instead of 12 feet above, we will have it 12 feet under
[21:18] <KiwiBruin> so
[21:18] <KiwiBruin> down
04[21:18] <@bloodysurgeon> since an electron will have a force down in a magnetic field pointing into the page
04[21:18] <@bloodysurgeon> last question before I end this discussion
[21:18] <cathyrn887> is we change the location of detector do we still need to change the arrangement of the battery
[21:19] <cathyrn887> *if
04[21:19] <@bloodysurgeon> very keen observation
04[21:19] <@bloodysurgeon> in the hypothetical situation i am just shooting it left to right
[21:20] <Chocolatebear89> so whats the point of the dectector? if we know all of the variables
04[21:20] <@bloodysurgeon> and we do not need to change the battery since the electic fiel will cancel out the magnetic field anyways
04[21:20] <@bloodysurgeon> we dont know ALL the variables
04[21:21] <@bloodysurgeon> we are looking for mass
04[21:21] <@bloodysurgeon> in a mass spec
04[21:21] <@bloodysurgeon> we shoot electrons onto a particle with unknown mass
[21:21] <cathyrn887> sorry but if bith field cancel how do we have a velocity
04[21:21] <@bloodysurgeon> and it breaks up into different smaller masses
[21:21] <Flapjacks> because particles are always moving
04[21:21] <@bloodysurgeon> v = E/B
04[21:22] <@bloodysurgeon> qvB, velocity is perpendicular to the electric field and magnetic field
[21:22] <cathyrn887> okay now i get it...both field don't equal each other in magnitude
04[21:23] <@bloodysurgeon> the fields could or could not, irrelevant, but the forces do equal each other
04[21:23] <@bloodysurgeon> now my last question
04[21:23] <@bloodysurgeon> in this situation
[21:23] <cathyrn887> okay
04[21:23] <@bloodysurgeon> what is the work done on an alpha particle by the magnetic field?
[21:24] <Flapjacks> 12
[21:24] <cathyrn887> zero
04[21:24] <@bloodysurgeon> yes zero
04[21:24] <@bloodysurgeon> im sorry let me correct a mistake i made on a previous statement
04[21:25] <@bloodysurgeon> nvm, no typo
04[21:25] <@bloodysurgeon> yes zero
[21:25] <Chocolatebear89> why is it zero?
04[21:25] <@bloodysurgeon> since the magnetic field is perpendicular
[21:25] <cathyrn887> what is nvm
04[21:26] <@bloodysurgeon> and W = F(in the direction of displacement) x d
04[21:26] <@bloodysurgeon> nvm = nevermind
[21:26] <Flapjacks> nvm = not very much
[21:26] <cathyrn887> lol thanx
[21:26] <KiwiBruin> lol flapjacks
04[21:26] <@bloodysurgeon> ok. this concludes my lesson
[21:27] <cathyrn887> what will the next lecture be on?
04[21:27] <@bloodysurgeon> it will be in chemistry
04[21:28] <@bloodysurgeon> if I teach it, it will be acid & bases

 

[loveoforganic]

Looks like the sessions are going well, if you're still doing them over the summer, I'll be attending. Thanks for posting.

 

[Protactinium]

Just so these threads don't get buried in obscurity, would it be possible to make a session sticky at the top linking these threads while providing rolling edits about new appointment times and updates?

 

[phEight]

These sessions do look to be tremendously helpful, I just don't have the time to attend these with finals going on and such. If these are going on this summer I'll definitely attend.

 

[ksmi117]

01[23:02] <@ksmi117> So first, welcome to the review session, yay!
[23:02] <@phosej> yay
01[23:03] <@ksmi117> As requested, we will be going over Electrochemistry
01[23:03] <@ksmi117> So throughout the lecture, I will ask questions
01[23:04] <@ksmi117> please feel free to answer them, I'm not going to call on anyone or anything
01[23:04] <@ksmi117> if you have any questions for me, you can ask me here or privately
01[23:05] <@ksmi117> that cool with everyone?
[23:05] <loveoforganic> si
01[23:06] <@ksmi117> ok, so the first step in understanding electrochemisty is understanding oxidation and reduction
01[23:07] <@ksmi117> so an oxidation number is how many electrons a particular atom is donating or accepting in a structure
01[23:07] <@ksmi117> so we have some rules for assigning oxidation numbers to atoms
01[23:08] <@ksmi117> these rules are in order of the most important to the least important
01[23:08] <@ksmi117> so if you are looking at a molecule and you cannot get the atoms to follow all the rules, you want to satisfy the first rule before the last
01[23:09] <@ksmi117> 1. any element in its standard state has an oxidation number of 0
01[23:10] <@ksmi117> 2. the sum of the oxidation numbers in a molecule equals the charge on that molecule
01[23:11] <@ksmi117> 3. Group I metals in a molecule (Na, K, etc) have an oxidation number of +1 and Group II metals (Ca, Mg, etc) have an oxidation number of +2
01[23:11] <@ksmi117> 4. Fluorine has an oxidation number of -1
[23:12] <icekream> do u get paid to do this
01[23:12] <@ksmi117> 5. Hydrogen has an oxidation number of +1 when bound to something more electronegative than C, 0 when bound to C, and -1 when bound to something less electronegative than C
01[23:12] <@ksmi117> no, I don't
[23:13] <icekream> damn, thats nice of u then
01[23:14] <@ksmi117> 6. oxygen has an oxidation number of -2 (except in peroxides - Na2O2 or H2O2 where it is -1)
[23:14] <icekream> can i ask a question?
01[23:14] <@ksmi117> yes
[23:14] <icekream> so for example, what would be the charges on CH3+
01[23:15] <@ksmi117> 7. The halogen family has an oxidation number of -1 and the oxygen family has -2
01[23:15] <@ksmi117> does anyone want to answer icekream's question before I do?
01[23:16] <@ksmi117> no, haha ok
[23:16] <loveoforganic> does the mcat tend to stick to the pretty standard molecules? e.g. would expecting to know the oxidation numbers on a superoxide surprise you?
[23:16] <loveoforganic> for ch3+, i'd say 0 for the hydrogens, +1 on the carbon
01[23:16] <@ksmi117> yes, that's right
[23:17] <icekream> dang, i would hvae said carbon is -2 and h is +1
01[23:17] <@ksmi117> and I'd say that the MCAT will generally stick to easier stuff just because they know it's timed and they don't want you to waste all of your time on something like figuring out oxidation numbers
01[23:18] <@ksmi117> it's more big picture than that
01[23:18] <@ksmi117> see, icekream in the rules it says that if H is bound to C it has an oxidation number of 0
01[23:18] <@ksmi117> so that leaves us with +1 on carbon
[23:18] <icekream> 'it' being hydrogen?
01[23:18] <@ksmi117> yes
[23:19] <icekream> ok thx
01[23:19] <@ksmi117> ok so those are our 7 rules
[23:19] <@phosej> ksmi i just have a question
01[23:19] <@ksmi117> yes?
[23:19] <loveoforganic> also, if you've taken organic, you can see that the carbon is the electron deficient atom
[23:19] <@phosej> how do oxidation numbers relate to formal charge?
[23:20] <loveoforganic> good q
01[23:20] <@ksmi117> they are not related but can be the same
[23:20] <loveoforganic> is it just inorganic/organic?
01[23:21] <@ksmi117> the formal charge equation is (Group Number of the Central Atom) - (Non-bonding Electrons) - 0.5(Shared Electrons)
01[23:21] <@ksmi117> loveoforganic, i don't understand your question
[23:22] <@phosej> okay thanks ksmi
[23:22] <loveoforganic> I was wondering if it was just a difference between the fields, because i've only learned about formal charge in organic and oxidation number in inorganic chem, but nvm, you answered it
01[23:22] <@ksmi117> ok
01[23:22] <@ksmi117>
01[23:22] <@ksmi117> ok, so now we must understand the concept of an oxidation/reduction (redox) reaction
01[23:23] <@ksmi117> a redox reaction is a rxn in which oxidation states of atoms change
[23:23] <icekream> could u incorporate more questions into this lecture, please?
[23:23] <icekream> ty
01[23:23] <@ksmi117> haha sure
01[23:24] <@ksmi117> so how does the oxidation number change in the oxidation part of a redox reaction?
01[23:24] <@ksmi117> your choices are - it increases or it decreases
[23:25] <@phosej> oxidation part means losing electrons, so it becomes more positive
[23:25] <loveoforganic> becomes more positive
[23:25] <loveoforganic> yeah
01[23:25] <@ksmi117> yes, even though you two didn't use my choices
[23:25] <icekream> lol
[23:25] <@phosej> increases/decreases could mean just magnitude
[23:25] <loveoforganic> exactly!
01[23:26] <@ksmi117> so that means the reduction half is the half-rxn in which the oxidation number decreases
01[23:26] <@ksmi117> oh fine haha the oxidation number becomes more negative in the reduction
01[23:27] <@ksmi117> so like phosej said oxidation is loss of electrons, and logically reduction would be the gain of electrons
01[23:27] <@ksmi117> so heres a reaction: Fe + 2HCl -> FeCl2 + H2
01[23:28] <@ksmi117> what is oxidized?
[23:28] <loveoforganic> iron
01[23:28] <@ksmi117> yes
01[23:28] <@ksmi117> and reduced?
[23:28] <@phosej> H
01[23:28] <@ksmi117> yes
[23:28] <icekream> man ur too quick
[23:29] <@phosej> Fe goes from 0 --> +2
01[23:29] <@ksmi117> now we can also write the above rxn in half reactions, where the atoms that don't change oxidation states are left out
[23:29] <@phosej> H goes from +1 --> 0
01[23:29] <@ksmi117> yep
[23:29] <@phosej> Cl- stays -1 ---> -1
[23:29] <@phosej> just for clarity
01[23:29] <@ksmi117> anyone wants to take a stab at the half reactions?
01[23:30] <@ksmi117> want*
[23:30] <icekream> fe loses 2 electrons
01[23:30] <@ksmi117> yes
[23:30] <icekream> h gains 1
[23:30] <loveoforganic> Fe -> Fe2+ +2e-, 2H+ + 2e- -> H2
[23:30] <icekream> cl stays the same
[23:31] <icekream> DAMN H GAINS 2
01[23:31] <@ksmi117> yep, loveoforganic got them
[23:31] <loveoforganic> H gains one
[23:31] <loveoforganic> 2 H's though
[23:31] <loveoforganic> in the product
01[23:31] <@ksmi117> yep
01[23:31] <@ksmi117> does that make sense icekream?
[23:32] <icekream> yes
01[23:33] <@ksmi117> ok, since I obviously can't draw on here, I'm gonna need y'all to look at this picture of a galvanic cell while I explain it
01[23:33] <@ksmi117> http://img34.imageshack.us/my.php?image=imgp0148.jpg
01[23:33] <@ksmi117> ok so this is a galvanic cell
[23:33] <icekream> ok
[23:34] <loveoforganic> could you repost the link please? refreshed to allow popups
01[23:34] <@ksmi117> http://img34.imageshack.us/my.php?image=imgp0148.jpg
[23:34] <loveoforganic> thanks
01[23:34] <@ksmi117> so a galvanic cell uses redox reactions to create an electrical current
01[23:35] <@ksmi117> some important things to remember...
01[23:35] <@ksmi117> 1. oxidation ALWAYS occurs at the anode
01[23:35] <@ksmi117> 2. likewise, reduction occurs at the cathode
[23:35] <loveoforganic> this is for a galvanic (voltaic) cell only, just to be clear
[23:36] <@phosej> RED CAT, AN OX is the mnemonic
01[23:36] <@ksmi117> so we have our half reactions from before (one being reduction and one being oxidation) occurring in the different half cells
01[23:36] <@ksmi117> so another picture:
01[23:37] <@ksmi117> http://img20.imageshack.us/my.php?image=imgp0149a.jpg01
[23:37] <@ksmi117> this is also a galvanic cell
01[23:37] <@ksmi117> just an example
01[23:38] <@ksmi117> the solution on the left is a ZnSO4 solution and on the right a CuSO4 solution
01[23:39] <@ksmi117> so the electrons from the oxidation travel along the wire to the cathode
[23:39] <@phosej> what's the significance of the solutions? (SO4) do they just have to agree?
[23:39] <loveoforganic> soluble salt that contains the respective metal ion
01[23:39] <@ksmi117> yes, they just need to contain the metal
[23:40] <@phosej> so if i used another solution without Zn2+ ions being released, the Zn strip wouldn't go to Zn2+?
[23:41] <loveoforganic> I don't think there'd be as much of a problem on the anode end, but you might have some conflicting reactions going on
01[23:41] <@ksmi117> good question
[23:41] <loveoforganic> because you have different redox potentials for the different metals
[23:42] <loveoforganic> like if you used silver nitrate as the solution, silver ion is pretty prone to being reduced
01[23:42] <@ksmi117> the reaction would still happen but like loveoforganic said, the two metals could react instead of the two halves of the cell
[23:43] <loveoforganic> if you don't want me to help with answers, please say so phose; it just helps me learn to try to explain it
01[23:43] <@ksmi117> so this whole problem of what would react with what brings us to the concept of reduction potentials
[23:43] <@phosej> no it's totally fine, i was just a little confused at the purpose of the solvent
01[23:43] <@ksmi117> in galvanic cells, you want your reaction to be spontaneous
01[23:45] <@ksmi117> ok so how you determine whether or not a reaction will be spontaneous is by finding the potential for the entire reaction
01[23:45] <@ksmi117> the potential for the reaction is the sum of the potentials of the half reactions
01[23:46] <@ksmi117> is the overall potential is positive, the rxn is _______
01[23:46] <@ksmi117> if*
[23:46] <loveoforganic> spontaneous
01[23:46] <@ksmi117> yep
[23:46] <@phosej> wait doesn't it depend on whether you're talking about reduction potentials or oxidation potentials?
[23:46] <loveoforganic> it's standard to list reduction potentials
[23:47] <loveoforganic> chances are if you see a list, it's reduction potentials
[23:47] <loveoforganic> but yes it would, i think
01[23:47] <@ksmi117> like so: http://img32.imageshack.us/my.php?image=imgp0147a.jpg
[23:47] <@phosej> but if we're looking at oxidation potentials, a negative potential is spontaneous?
[23:47] <loveoforganic> that sounds right to me
03[23:47] * ezprey ([email protected]) has joined #mcat
01[23:48] <@ksmi117> you need to find the reduction potential for the reduction rxn and the oxidation potential for the oxidation rxn and add those
01[23:48] <@ksmi117> in the table I linked it gives all reduction potentials
01[23:48] <@ksmi117> so the more positive, the more likely it would be to be reduced
01[23:48] <@ksmi117> flip all the reactions around and change the signs
01[23:49] <@ksmi117> and you have your oxidation potentials
01[23:49] <@ksmi117> again the more positive it is, the more likely it will be oxidized
[23:49] <loveoforganic> reduced?
01[23:50] <@ksmi117> no, so say we take the first thing on the list
01[23:50] <@ksmi117> Li+ + e- -> Li
[23:51] <loveoforganic> right, it's very negative, so it would be prone to oxidation
01[23:51] <@ksmi117> right
[23:51] <loveoforganic> sorry, were you still talking about oxidation potentials?
01[23:51] <@ksmi117> what I'm saying is after you flip the reaction: Li -> Li+ + e-
01[23:51] <@ksmi117> it's very positive
[23:51] <loveoforganic> got it, sorry
01[23:51] <@ksmi117> yes
01[23:52] <@ksmi117> it's hard to explain over chat
01[23:52] <@ksmi117> so we all on the same page now?
[23:52] <@phosej> so for Li + e- : the reduction is NONspontaneous, but for Li : the oxidation is spontaneous
[23:52] <@phosej> is that correct?
[23:52] <loveoforganic> it would depend what you're comparing it to
01[23:52] <@ksmi117> yes, no reduction or oxidation is going to happen alone
01[23:53] <@ksmi117> thats why its called a redox reaction
[23:53] <@phosej> ah well how about comparing it to standard hydrogen electrode
01[23:53] <@ksmi117> then yes
[23:53] <@phosej> okay thanks it's clear now
01[23:54] <@ksmi117> ok so back to picture number two...
01[23:54] <@ksmi117> http://img20.imageshack.us/my.php?image=imgp0149a.jpg
01[23:54] <@ksmi117> well you need picture 3 as well
[23:54] <ezprey> hehe did you take these of your book with your camera?
01[23:54] <@ksmi117> http://img32.imageshack.us/my.php?image=imgp0147a.jpg
01[23:55] <@ksmi117> yes, since i can't draw through chat
[23:55] <ezprey> nice
01[23:55] <@ksmi117> so what is the oxidation potential at the anode?
[23:56] <ezprey> +0.76
01[23:56] <@ksmi117> yes
[23:56] <ezprey> you reverse the reduction potential
01[23:56] <@ksmi117> and the reduction potential at the cathode?
[23:56] <loveoforganic> .34
01[23:56] <@ksmi117> yes
[23:56] <ezprey> yeah +0.34
01[23:56] <@ksmi117> so the overall potential is what?
[23:57] <loveoforganic> 1.1
01[23:57] <@ksmi117> and is this a spontaneous rxn?
[23:57] <ezprey> 0.76+0.34 = +1.1 spontaneous
01[23:57] <@ksmi117> right
01[23:57] <@ksmi117> so we all also know that a reaction is spontaneous when is free energy change (deltaG) is what?
[23:58] <loveoforganic> negative
01[23:58] <@ksmi117> right
[23:58] <loveoforganic> why is that again?
[23:58] <loveoforganic> conceptually
01[23:58] <@ksmi117> so it makes sense that deltaG = -n*F*E
[23:58] <ezprey> dG = dH - TdS
01[23:59] <@ksmi117> a reaction will never just absorb energy on its own
[23:59] <loveoforganic> ok, that makes sense, thanks
Session Time: Fri May 29 00:00:00 2009
01[00:00] <@ksmi117> ok in the above formula: n is the number of moles of electrons involved in the redox reaction
01[00:00] <@ksmi117> and F is the charge of one mole of electrons, 96000 C/mol e-
01[00:01] <@ksmi117> E is the potential of the cell
01[00:01] <@ksmi117> so what would the free energy change be in our galvanic cell?
[00:02] <loveoforganic> -220000
[00:02] <loveoforganic> about?01
[00:02] <@ksmi117> yep
[00:02] <ezprey> what's the calculation?
[00:02] <ezprey> 2 * 96000*1.1?
01[00:03] <@ksmi117> remember you won't have a calculator on the MCAT so you can round 96000 to 100000
[00:03] <loveoforganic> negative of that
01[00:03] <@ksmi117> and then pick the closest answer
[00:03] <ezprey> right
[00:03] <ezprey> i'm just scared of big numbers haha
[00:03] <loveoforganic> yeah, mental math = -_-
[00:03] <loveoforganic> used to the calculator crutch
01[00:04] <@ksmi117> ok, also another thing to remember when dealing with potentials
01[00:04] <@ksmi117> the potential is intrinsic to the material
01[00:05] <@ksmi117> so it doesn't matter how much you have
01[00:05] <@ksmi117> the potential will always be the same
[00:05] <loveoforganic> so
[00:05] <ezprey> should we learn how to balance redox reactions for the mcat?
[00:05] <loveoforganic> if you had a reaction
01[00:05] <@ksmi117> so Li+ + e- -> Li has a potential of -3.05 V
01[00:06] <@ksmi117> and 2Li+ + 2e- -> 2Li also has a potential of -3.05 V
01[00:06] <@ksmi117> yes, you should know how to balance them
[00:06] <loveoforganic> that didn't have an equal electron transfer, i.e. half reactions had to be balanced, say iron reacting with acid with you ending up with Fe3+
[00:06] <loveoforganic> what would you use for n?
01[00:06] <@ksmi117> n would be 2 in that case
01[00:07] <@ksmi117> free energy change depends on the amount
01[00:07] <@ksmi117> but potential does not
[00:07] <loveoforganic> 2Fe + 3HCl -> 2Fe3+ + 2H2, right?
[00:07] <loveoforganic> oops, no
01[00:07] <@ksmi117> wait i missed something
01[00:07] <@ksmi117> hold on
01[00:07] <@ksmi117> sorry
[00:08] <ezprey> love can you clarify your question?
01[00:08] <@ksmi117> wait... that's not balanced
[00:08] <loveoforganic> i know lol, i misbalanced
[00:09] <loveoforganic> "oops, no"
[00:09] <loveoforganic> sure ezprey, one sec
[00:09] <loveoforganic> You have 2 half reactions. Unbalanced, one reaction gives up 3 electrons. The other reaction takes 2 electrons.
[00:10] <loveoforganic> What would n be in that case?
[00:10] <ezprey> my instinct is that you balance
[00:10] <ezprey> then get the n there
01[00:10] <@ksmi117> How about 2Au + 3CuCl2 -> 2AuCl3 + 3Cu?
[00:10] <loveoforganic> n would be 6 then?
01[00:10] <@ksmi117> like that?
[00:10] <loveoforganic> yes, that looks good
01[00:11] <@ksmi117> yes n is 6
[00:11] <loveoforganic> ok, thanks
01[00:11] <@ksmi117>
01[00:11] <@ksmi117> ok did everyone else kind of follow that?
01[00:12] <@ksmi117> your two half reactions in this reaction are:
[00:12] <ezprey> okay so that rule always works? lets say i had one that gave up 4, another took 2, n = 8? just multiply?
[00:12] <loveoforganic> no
01[00:12] <@ksmi117> no, it would be 4
[00:12] <loveoforganic> you'd end up balancing at 4 in that case
01[00:12] <@ksmi117> correct
01[00:13] <@ksmi117> you always want to use the balanced reaction where the coefficients have no common factors
01[00:13] <@ksmi117> except 1 of course
[00:13] <ezprey> ah right... but if one gave up 5, another took 2, then n = 10 in that case
01[00:13] <@ksmi117> yes
01[00:14] <@ksmi117> so least common multiple of the two
01[00:16] <@ksmi117> ok so, is everyone clear on the galvanic cells? and determining whether or not a reaction will take place in them?
[00:16] <loveoforganic> yes
01[00:17] <@ksmi117> ok since i hear no "no"'s i'll assume so
01[00:17] <@ksmi117>
01[00:17] <@ksmi117> next we have the electrolytic cell
01[00:17] <@ksmi117> in an electrolytic cell, we use an external voltage source like a battery to create a current that forces a non-spontaneous reaction to occur
01[00:18] <@ksmi117> http://img11.imageshack.us/my.php?image=imgp0141e.jpg
[00:18] <loveoforganic> for the terminology in electrolytic cells, do you use anode/cathode as if the cell was voltaic?
01[00:19] <@ksmi117> the anode is the site of oxidation, and the cathode is reduction
[00:19] <loveoforganic> ok, thanks
01[00:19] <@ksmi117> so in this picture, the anode is on the right
01[00:20] <@ksmi117> since Cl- is being oxidized
[00:20] <loveoforganic> why is there no need for a salt bridge in this instance?
01[00:21] <@ksmi117> since the reaction isnt spontaneous, we dont need to separate them
[00:21] <loveoforganic> oh, same container, right
01[00:21] <@ksmi117> the salt bridge in the galvanic cell is to allow for the charge to flow back through the system without the two half cells touching
01[00:23] <@ksmi117> ok so if we had the potentials for these half reactions (which we don't in our chart) we would see that the overall reaction 2NaCl -> 2Na + Cl2 is not spontaneous
01[00:23] <@ksmi117> but we can use our brains for that one, our table salt doesnt spontaneously turn to Na and chlorine gas
01[00:24] <@ksmi117> so the electrolytic cell creates a flow of electrons from the anode to the cathode
01[00:25] <@ksmi117> the voltage of the battery used must be at least enough to cancel out the negative potential of the reaction
01[00:26] <@ksmi117> so say this reaction has an overall potential of -4 V (just making up a number here), then our battery must be greater than +4 V to make the total cell potential (reaction potential + battery voltage) greater than 0
[00:27] <ezprey> is it 4 or greater or greater than 4?
[00:28] <loveoforganic> infintesimally greater than 4, to run
[00:28] <loveoforganic> probably butchered that word
[00:28] <loveoforganic> sorry, wasn't clear
01[00:28] <@ksmi117> if it was 4 the total cell would have a potential of 0 which would give a free energy change of 0
[00:28] <loveoforganic> an infinitely small amount, greater than 4
01[00:28] <@ksmi117> so it'd be in that weird limbo of being neither nonspontaneous nor spontaneous
01[00:29] <@ksmi117> so greater than 4
[00:29] <ezprey> okay cool, got it
[00:29] <@phosej> i think at 4, the cell would be at equilibrium so it wouldn't run
01[00:30] <@ksmi117> so other than using an external voltage, the electrolytic cell acts in the same way a galvanic cell does
[00:30] <@phosej> delta G = 0 by definition is equilibrium condition...
[00:30] <loveoforganic> sounds right to me
01[00:30] <@ksmi117> right
01[00:31] <@ksmi117> ok so overall comparisons of galvanic vs. electrolytic cells:
01[00:31] <@ksmi117> in both, the anode is oxidaton and the cathode is reduction
01[00:31] <@ksmi117> in both, the flow of electrons is from the _____ to the ______
[00:32] <loveoforganic> anode, cathode
01[00:32] <@ksmi117> right
01[00:32] <@ksmi117> so knowing that in a galvanic cell electrons spontaneously move to the cathode, which electrode is positive?
[00:33] <@phosej> one thing: why is it that in galvanic cells the cathode is +, anode -, but in electrolytic cells, the cathode is - and anode +?
01[00:33] <@ksmi117> thats what I'm getting at now
[00:33] <@phosej> ah okay so the answer to your question is that the cathode is positive
01[00:34] <@ksmi117> you can tell by which way the electrons want to move
01[00:34] <@ksmi117> yep
[00:34] <@phosej> since electrons are moving/attracted to it
[00:34] <loveoforganic> is that really valid?
[00:34] <loveoforganic> electron pull doesn't necessarily correspond to charge
01[00:34] <@ksmi117> normally we associate positive with cathode, but in the electrolytic cell its not the case
01[00:34] <@ksmi117> thats how I learned it
[00:35] <@phosej> the way i think about it
01[00:35] <@ksmi117> I don't know any other way to validate it
01[00:35] <@ksmi117> sorry
[00:36] <loveoforganic> it's fine, I know it's that way by convention
[00:36] <@phosej> actually i don't have a way of understanding it, just remembering it
01[00:36] <@ksmi117> ok so that about wraps it up
01[00:36] <@ksmi117> yay electrochemistry
[00:37] <ezprey> cool thanks ksmi
[00:37] <ezprey> sorry i was late
[00:37] <@phosej> yeah thanks a ton ksmi
01[00:37] <@ksmi117> I hope this was helpful
[00:37] <loveoforganic> thanks for the help,^^
01[00:37] <@ksmi117> I'll post a copy of this in the forums for all the people that couldn't be here01[00:37] <@ksmi117> and you can check out the first half ezprey
[00:37] <@phosej> anyone have any questions on this stuff?
01[00:38] <@ksmi117> any other questions for me?
[00:38] <loveoforganic> one quick thing - is it necessary to be able to predict the products in a redox reaction?
[00:38] <loveoforganic> say, KMnO4 reacting with iron in acidic solution?
01[00:38] <@ksmi117> what do you mean? if they give you some reactants, do you need to be able to say what the product would be?
[00:39] <loveoforganic> yeah
01[00:39] <@ksmi117> oh, i would think that they would tell you what it would create
[00:39] <loveoforganic> ok, thanks01[00:39] <@ksmi117> or at least give you some hints to help you figure it out
01[00:40] <@ksmi117> like say there is a color change or a ppt forms or something like that
[00:40] <loveoforganic> ah ok, thanks

 

[Dr Gerrard]

How can you tell the produce from a change in color?

 

[MSUSpartan642]

When are more of these going to be going on? I would love to join in on the sessions and review some topics with everyone!

 

[ksmi117]

How can you tell the produce from a change in color?

If they were to give you a question like that it'd be an obvious one, like Cu is red while Cu2+ is blue in solution. It's unlikely that they would give you a question like that, but it's possible.

 

[ksmi117]

The next review session will take place on Thursday, June 4 at 11 PM CST in the SDN MCAT chatroom.

Here is a link to a poll about what topic you the people want covered: http://forums.studentdoctor.net/showthread.php?t=632510

 

[kwokkit]

Posting for loveoforganic

[00:05] <ladygwennie> Thanks and hi!
[00:05] <loveoforganic> howdy!
[00:05] <loveoforganic> you here for the review too ybl?
[00:05] <YBL> yup

[00:06] <loveoforganic> arighty, well it's past 11, so I guess i'll go ahead and start
[00:06] <loveoforganic> the chosen topic for tonight was oxygen containing compounds, so i'll lecture some on that
[00:07] <loveoforganic> if at any point you'd like me to come up with some sort of problem for you to work, just ask
[00:07] <loveoforganic> if you have any questions, please ask!
[00:07] <ladygwennie> ok thanks

[00:07] <loveoforganic> after I finish going over oxygen containing compounds, i'll take a q and a on other topics
[00:08] <loveoforganic> 1) There are several classes of oxygen containing compounds 2013 alcohols, ethers, and carbonyls. All of these compounds have polarized bonds, due to the greater electronegativity of oxygen relative to carbon.
[00:08] <loveoforganic> 2) Alcohols are compounds with the connectivity R-OH. They are classified based on the number of alkyl substituents on the R. One alkyl substituent gives a primary alcohol, two gives a secondary alcohol, and three a tertiary alcohol.
[00:08] <loveoforganic> by the way, ignore the numbers at the start, I pretyped some of this out and am copy pasting
03[00:09] * hotinhere38 ([email protected]) has joined #mcat
[00:09] <loveoforganic> 3) Due to the amphoteric nature of alcohols (exhibiting properties of both acids and bases), they exhibit extensive hydrogen bonding. Due to this, they have significantly higher boiling points than alkanes of similar molecular weight
[00:09] <loveoforganic> hey hot, lecture's already underway
[00:09] <hotinhere38> ok
[00:10] <loveoforganic> 4) Again, alcohols can act as both weak acids and weak bases. They have a pKa similar to that of water. The acidity depends both on the number of alkyl substituents and the atoms bonded to those substituents.
[00:10] <loveoforganic> 5) Alkyl groups are inductively electron donating. They contribute electron density to the oxygen and thus strengthen the O-H bond. For this reason, the acidity of alcohols with unsubstituted alkyl substituents is in the order tertiary < secondary < primary.
[00:11] <loveoforganic> 6) When comparing alcohols of identical alkyl substitution, i.e. primary vs primary, acidity can be affected due to the substituents on the alkyl group
[00:11] <loveoforganic> Electronegative substituents such as fluorine inductively withdraw electrons from oxygen, weakening the O-H bond and thus increasing the acidity. The more electronegative the substituent and the nearer it is to the oxygen, the more effect it has.
----------disconnected for a little bit here--------------
[00:13] <YBL> 2- fluoropropanol?
[00:13] <ladygwennie> 2-flu
[00:13] <loveoforganic> yes, good
[00:13] <loveoforganic> one more, a little trickier
02[00:13] * ezprey1 ([email protected]) Quit (Operation timed out)
[00:14] <loveoforganic> 1-fluoroisopropanol, 2-fluoropropanol, 1-fluoropropanol
[00:14] <loveoforganic> which is most acidic?
[00:15] <ladygwennie> 1-flu?
[00:15] <loveoforganic> which one?
[00:15] <ladygwennie> not iso sorry
01[00:15] <ezprey> 1fluoropropanol
[00:15] <ladygwennie> 1-fluoropropanol[00:15] <loveoforganic> yes good; and between the other two?
[00:16] <ladygwennie> hmmmm
[00:17] <ladygwennie> 2-fluoroproanol i think
[00:17] <loveoforganic> that's right, can you give your reasoning?
[00:17] <ladygwennie> The iso compound has higher substitution than the others
[00:18] <loveoforganic> good, and because the alkyl groups are electron donating, they serve to destabilize the conjugate base of the alcohol
[00:18] <ladygwennie>

[00:18] <loveoforganic> 7) Phenol, a phenyl alcohol, is markedly more acidic than alkyl alcohols; pKa about 10, instead of 15-18. This is because the phenoxide anion (deprotonated phenol) is resonance stabilized.
[00:19] <loveoforganic> Like alkyl alcohols, electronegative subsituents on the aromatic ring of phenols increase the acidity due to inductive effects.
[00:19] <loveoforganic> 8) However, much larger effects are seen due to resonance
[00:19] <loveoforganic> Substituents that are resonance electron withdrawing, when in the ortho- or para- position, provide an additional stable resonance structure to delocalize the phenoxide2019s negative charge. Likewise, resonance electron donators decrease acidity due to the electrostatic repulsion of adjacent lone pairs.
[00:20] <loveoforganic> keep in mind that the pKa difference between phenol and alkyl alcohols (5-8) indicates that the phenol is 10^5 to 10^8 times more acidic
[00:21] <loveoforganic> resonance stabilization is a very large contributor
[00:21] <loveoforganic> rank the acidity of these alcohols
[00:22] <loveoforganic> p-nitrophenol, o-methoxyphenol (aka o-hydroxyanisole), t-butanol
01[00:23] <ezprey> nitrophenol, methoxyphenol, t-butanol
01[00:24] <ezprey> am i right?
[00:24] <loveoforganic> that's right
01[00:24] <ezprey> nitrophenol because the NO2 is electron withdrawing
01[00:24] <ezprey> stabilizing the formation of a - charge
01[00:24] <ezprey> methoxy is second because phenols are much more acidic than alcohols
[00:25] <loveoforganic> good
[00:25] <loveoforganic> one more question
[00:25] <loveoforganic> what is the order of acidity of these compounds?
[00:26] <loveoforganic> 3,5-dinitrophenol, o-nitrophenol, p-methoxyphenol
01[00:27] <ezprey> as you've written them, highest to lowest
[00:27] <loveoforganic> anyone else?
[00:28] <ladygwennie> I agree
[00:28] <loveoforganic> incorrect
[00:28] <YBL> are the first 2 switched?
[00:28] <ladygwennie> is o-nitro, pmeth, 3.5
[00:28] <loveoforganic> yes ybl, and no lady
[00:28] <ladygwennie> ahhh ok
[00:28] <loveoforganic> can you explain why ybl?
[00:29] <YBL> in 3,5 dinitro the nitro groups are in the meta positions
[00:30] <YBL> so that decreases the stabilizationsom
[00:30] <loveoforganic> partially right
[00:30] <YBL> some how... im not really that sure
[00:31] <loveoforganic> while in the meta position, the nitro groups do withdraw electron density from the aromatic ring, and thus, they do stabilize the negative charge of the phenoxide ion
[00:31] <loveoforganic> however, the nitro group, and other resonance electron withdrawing groups, can only provide additional resonance structures to delocalize the negative charge of the phenoxide while in the ortho or para position
[00:32] <loveoforganic> my internet browser is being difficult and won't let me open a new browser page, need to grab my laptop so I can post a link to better explain
[00:32] <loveoforganic> one sec
[00:33] <loveoforganic> while you wait, please get a sheet of paper and try to draw out all the resonance structures of phenoxide
[00:34] <loveoforganic> http://www.angelo.edu/faculty/kboudrea/molecule_gallery/06_phenols/phenol_02.gif
[00:35] <loveoforganic> as you can see in the link, if you haven't already drawn it out, the lone pair carrying the negative charge is able to delocalize only into the ortho and para positions on the ring
[00:36] <loveoforganic> is anyone unclear on this?
[00:36] <loveoforganic> or is anyone still working it out?
01[00:36] <ezprey> i thought that the NO2 would kind of act throughout the ring though
[00:37] <loveoforganic> http://images.absoluteastronomy.com...re/resonance_contributors_of_nitrobenzene.jpg
01[00:37] <ezprey> i see what you're saying, how the - charge can't make it on the same carbon that is attached to the nitro groups in the 3,5 case
[00:38] <loveoforganic> do you see in that link why the positive charges are where they are?
02[00:38] * ladygwennie ([email protected]) Quit (Client exited)
01[00:39] <ezprey> yep i see how that works
[00:39] <loveoforganic> do you see how that correlates to the substituted phenoxide? if not I can draw it out and scan it
01[00:39] <ezprey> but that's not a phenol molecule...
[00:39] <loveoforganic> ok, i'll draw it, just a sec
01[00:39] <ezprey> i'm just a little confused now
[00:39] <loveoforganic> no worries
01[00:40] <ezprey> i should look at one case where its 1 NO2 group on para and one case where 2 NO2 groups on meta (phenol in both cases)?
[00:41] <loveoforganic> don't mind that there were 2 in that case, that was just intended to make the question a little tricky
[00:43] <loveoforganic> scanning now
01[00:44] <ezprey> haha okay
01[00:44] <ezprey> but i drew it myself
[00:44] <loveoforganic> which did you draw?
01[00:44] <ezprey> for the ortho one i see that the - charge is on the same carbon as the NO2 group
01[00:44] <ezprey> while for meta NO2 groups, the - charge can never get on that carbon
[00:44] <loveoforganic> yes, now, while that negative charge is on the carbon adjacent to the nitro group
01[00:45] <ezprey> therefore, less stabilization of the negative charge due to proximity to the electron withdrawing group
[00:45] <loveoforganic> not exactly
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[00:45] <loveoforganic> do you know what a nitro group looks like?
[00:45] <phatib> NO2
[00:45] <loveoforganic> http://upload.wikimedia.org/wikipedia/commons/d/dc/Nitro-group.png
[00:45] <loveoforganic> that specific structure
[00:46] <loveoforganic> do you see an additional resonance structure you could draw while the lone pair is adjacent to the nitro group?
[00:46] <phatib> yes
[00:46] <YBL> maybe we can all join an online whiteboard thing? like skrbl?
[00:46] <YBL> to make this easier?
[00:47] <loveoforganic> I'd be up for that, didn't know there was such a thing
[00:47] <phatib> http://upload.wikimedia.org/wikiped...800px-Nitro_group_resonance_structure.svg.png
[00:47] <phatib> just look at this pic
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01[00:48] <ezprey> i know all the resonance structures
[00:48] <loveoforganic> then you should see it's not just proximity
[00:48] <loveoforganic> the lone pair can form a double bond to the nitro nitrogen, and you end up with a negative charge on each nitro oxygen
[00:49] <loveoforganic> it's not the proximity, but the additional resonance structures that a resonance EWG provides while in the o- or p- position that provides the additional stability for the phenoxide
[00:49] <loveoforganic> does that make sense?
01[00:51] <ezprey> okay i'm confused at the phenol AND NO2 combination
[00:51] <loveoforganic> ok, let's all join a whiteboard
01[00:51] <ezprey> in the case where the OH loses the H, has - resonance
[00:51] <loveoforganic> ybl, you said you knew of one?
01[00:51] <ezprey> then the NO2 group displays + charge resonance
[00:51] <YBL> http://www.scriblink.com/index.jsp?act=phome&roomid=739&KEY=E4285D1F583AC985FE3573EB89F3B4A2
[00:52] <loveoforganic> ok, ezprey, you in?
01[00:54] <ezprey> yeah
01[00:55] <ezprey> whoa it's so clear now
[00:55] <loveoforganic> ok good
01[00:55] <ezprey> and this doesn't work for meta position huh
03[00:55] * phatib ([email protected]) has left #mcat
[00:55] <loveoforganic> right, remember the phenoxide resonance structures?
[00:56] <loveoforganic> the electron pair only bounced to the o and p positions
[00:56] <loveoforganic> does it make sense?
[00:57] <loveoforganic> the electron pair has no way to make resonate onto the nitro group while the nitro group is meta to the alcohol
[00:58] <YBL> yep.
[00:58] <loveoforganic> good with you too ezprey?
01[00:59] <ezprey> yep
[00:59] <loveoforganic> good deal
[00:59] <loveoforganic> if you lose it, i'll go back over it toward the end
[00:59] <loveoforganic> 9) Now on to the synthesis of alcohols. The most common synthesis route is via alkenes. Oxymercuration/reduction yields an alcohol from an alkene with Markovnikov regioselectivity 2013 the alcohol goes on the more substituted carbon of the alkene. The alcohol and hydrogen are added to the alkene trans. Oxymercuration/reduction is a two-step reaction. The first step uses Mercury (II) Acetate in water. The second step uses Sodium B
[01:00] <loveoforganic> the reason for the Markovnikov regioselectivity is that the reaction proceeds with a carbocation intermediate
[01:01] <loveoforganic> the organomercury compound adds to the less substituted carbon in order to yield the most stable carbocation intermediate
[01:02] <YBL> i thought this reaction went thru a cyclic intermediate
[01:02] <loveoforganic> sorry, that's a little bit incorrect
[01:02] <YBL> rather than a carbocation
[01:02] <loveoforganic> you're right ybl
[01:03] <loveoforganic> it's a mercurinium intermediate; the larger portion of the positive charge is held on the more substituted carbon
[01:03] <loveoforganic> for this reason, water (eventually the alcohol) adds to the more substituted carbon
[01:04] <loveoforganic> it adds in a trans fashion because the the cyclic mercurinium ion blocks the face it added to
[01:04] <loveoforganic> problem time
[01:05] <loveoforganic> what would be the iupac name of the compound formed by the oxymercuration/reduction reaction of 1-methylcyclohexene
[01:06] <YBL> 1-methylcyclohexanol
[01:07] <loveoforganic> that's correct
[01:07] <loveoforganic> 10) The complement to Oxymercuration/reduction is Hydroboration/oxidation. This reaction yields an alcohol from an alkene with non-Markovnikov regioselectivity. The hydrogen and alcohol are added to the alkene cis. It too is a two-step reaction. The first step is Borane in tetrahydrofuran. The second step is hydrogen peroxide in basic solution.
[01:08] <loveoforganic> the reason that this reaction yields the non-markovnikov product is it proceeds by a concerted mechanism
[01:08] <loveoforganic> the boron and hydrogen of borane add simultaneously to the alkene, and thus in a syn fashion
[01:09] <loveoforganic> due to the fact that the boron with two hydrogens attached to it is more sterically large than a single hydrogen, the boron adds to the less substituted carbon
[01:10] <loveoforganic> the boron is eventually replaced by a hydroxyl in the oxidation step, and thus the alcohol is in the non-markovnikov position
[01:10] <loveoforganic> problem time
[01:11] <loveoforganic> 1-methylcyclohexene undergoes a hydroboration/oxidation reaction; what is the iupac name of the product?
[01:11] <YBL> 2-methylcyclohexanol
[01:12] <loveoforganic> cis/trans?
[01:12] <YBL> cis
[01:12] <loveoforganic> incorrect
[01:12] <loveoforganic> remember, the hydrogen and boron add in a syn fashion, so they are on the same side of the product
[01:13] <YBL> ok
[01:13] <loveoforganic> makes sense?
[01:13] <YBL> yep
[01:14] <loveoforganic> Other synthesis routes for alcohols include the reduction of carbonyl compounds with sodium borohydride or lithium aluminum hydride, and the addition of Grignard reagents to carbonyl compounds, followed by treatment with a proton source.
[01:14] <loveoforganic> the mechanism of these reactions is more into carbonyl chemistry, so i can either discuss it now or wait til carbonyls and go back to it, which would you prefer?
[01:15] <YBL> it doesn't matter to me, whichever
[01:16] <loveoforganic> ezprey, you still around?
[01:16] <loveoforganic> arighty, i'll come back to it
01[01:16] <ezprey> come back to it
[01:16] <loveoforganic> The common reactions of alcohols involve substitution, elimination, and oxidation. Because OH- is a very poor leaving group, alcohols will not undergo substitution as is. For this reason, it must be chemically converted to a better leaving group. Tertiary alcohols can undergo direct reaction with HCl, HBr, or HI to yield the respective halide where the alcohol was, in an SN1 manner.
[01:17] <loveoforganic> the strong acid protonates the alcohol, and thus water is the leaving group (a very, very good leaving group)
[01:17] <loveoforganic> the counterion of the acid (Cl-, Br-, I-) can then add to the carbocation
[01:18] <loveoforganic> Primary and secondary alcohols are unable to undergo this SN1 style reaction. Treatment with thionyl chloride or phosphorus tribromide yields the respective halide in an SN2 manner (stereochemistry inverted).
[01:19] <loveoforganic065> not sure what happened, sorry
[01:20] <YBL> lol, its ok
03[01:20] * loveoforganic ([email protected]) has joined #mcat
[01:20] <loveoforganic> ok, anyway
[01:21] <loveoforganic> the mechanism for the treatment of an alcohol with PBr3 or thionyl chloride is pretty invovled
[01:21] <loveoforganic065> just keep in mind that the use of these reagents converts the alcohol into a good leaving group
[01:22] <loveoforganic065> however, due to the instability of secondary/primary carbocations
[01:22] <loveoforganic065> the now good leaving group doesn't dissociate on its own
[01:23] <loveoforganic065> the respective halide, either Cl- or Br- depending on thionyl chloride/phosphorus tribromide, attacks in an sn2 manner
[01:23] <loveoforganic065> ok, problem
[01:24] <loveoforganic065> you react R-3-butanol with thionyl chloride
[01:24] <loveoforganic065> what is your product
01[01:25] <ezprey> R-3???
[01:25] <loveoforganic065> R refers to the stereochemistry
01[01:25] <ezprey> how can it have R/S designation
01[01:25] <ezprey> doesn't have 4 diff. substituents...
[01:26] <loveoforganic065> well, it would actually be R-2-butanol, misnamed
[01:26] <loveoforganic065> but that doesn't make a difference
[01:26] <loveoforganic065> the carbon with the hydroxyl attached also has a methyl group, ethyl group, and hydrogen
[01:27] <loveoforganic065> 4 different substituents
[01:27] <YBL> S-2-chlorobutane?
[01:27] <loveoforganic065> that's right
[01:28] <loveoforganic065> once converted into an alkyl halide, the compound now has a plethora of compounds it can be made into by SN2 mechanism
[01:28] <loveoforganic065> onto eliminations
[01:28] <loveoforganic> There are multiple routes of elimination reactions for alcohols, but the most common is treatment with concentrated sulfuric acid. This elimination typically follows an SN1 mechanism for tertiary and secondary alcohols, and an SN2 mechanism for primary alcohols.
[01:29] <loveoforganic065> for the same reason as before, the secondary/primary alcohols undergo SN2-like mechanisms because the primary/secondary carbocation intermediates are typically too unstable to exist
[01:30] <loveoforganic065> the noteable exception to this is when the alcohol is in the allylic position. due to resonance stabilization of the cation, this could even be a primary carbon and still undergo an SN1 mechanism
[01:31] <loveoforganic> Alcohol oxidation can yield one of three products 2013 a ketone, aldehyde, or carboxylic acid. Tertiary alcohols do not undergo oxidation reactions. Secondary alcohols will always react to form ketones. Primary alcohols are where you need to know the reactants.
[01:32] <loveoforganic> Aldehydes are reactive species. To oxidize only to an aldehyde, you need a gentle oxidizing agent such as pyridinium chlorochromate (PCC). To obtain a carboxylic acid, a number of stronger oxidizing agents can be used.
[01:32] <loveoforganic065> this wraps up alcohols
[01:32] <loveoforganic> The second class of oxygen containing compound we2019ll discuss are ethers. Ethers have the structure R-O-R2019. They are a generally bland, unreactive functional group. The only significant reaction of straight-chain ethers is cleavage with strong acid. The mechanism of this cleavage (SN1 or SN2) depends on the structure of the ether.
[01:33] <loveoforganic> Epoxides are a special class of ethers, however, and do have some reactivity. Epoxides are ethers that have cyclopropane connectivity. This reactivity is attributed to the strain of the three-membered ring.
[01:34] <loveoforganic065> the carbon-oxygen bond in this case is very weak, due to the high deviation from the ideal 109.5o angle
[01:34] <loveoforganic> 19) Epoxides are susceptible to attack by nucleophiles at the ring carbons, by both SN1 and SN2 mechanisms. When the nucleophile is in basic solution, the mechanism will be SN2. In acidic solution, it2019s a little complex and undergoes a bit of a hybrid of SN2/SN1. I doubt that2019s necessary knowledge, however.
[01:34] <loveoforganic065> Just keep in mind that the carbons of epoxides are susceptible to nucleophilic attack
[01:35] <loveoforganic065> are there any questions on these topics before I move on?
[01:35] <YBL> nope
[01:35] <loveoforganic065> you good ezprey?
[01:37] <loveoforganic065> moving on
[01:37] <loveoforganic> Now on to the most interesting and diverse class of oxygen-containing compounds - carbonyls! Carbonyl compounds are those compounds with a C=O bond. The reactivity of these compounds is dominated by the polarization of this double bond. The carbon exhibits a partial positive charge, and the oxygen exhibits a partial negative charge.
[01:37] <loveoforganic> Because of this polarity, the carbonyl carbon is very susceptible to attack by nucleophiles. Following nucleophilic attack, carbonyl compounds can undergo either elimination of a leaving group, or require protonation of the oxygen to form a neutral alcohol. The specific reactivity of carbonyl compounds depends on what exactly is attached to the carbonyl carbon.
[01:38] <loveoforganic> If there is no good leaving group attached to the carbonyl carbon, protonation of the oxygen following nucleophilic attack will be the only way for the reaction to proceed. This is the case in ketones and aldehydes. If a good leaving group is attached to the carbonyl carbon, nucleophilic substitution is more likely to proceed.
[01:39] <loveoforganic> That is, the nucleophile will add to the carbonyl carbon, followed by the elimination of one of the original substituents on the carbonyl carbon. This is seen in the carboxylic acid derivatives, e.g. acyl halides, acid anhydrides, etc.
[01:39] <loveoforganic> 23) At this point, I feel the amount of information on these topics is pretty enormous and could go any number of direction, so I2019d like to have the direction chosen by you. So, what exactly carbonyl-related would you like to talk about? There2019s reactivity of specific carboxylic acid derivatives, alpha proton acidity, acetal formation, etc.
[01:40] <loveoforganic> if neither of you have any questions on carbonyl chemistry or alcohols/ethers/epoxides, we can just move on to random q and a

Not many q's afterwards, getting late