How much equations and constants are necessary to be memoriezed?

[CANgnome]

I am wondering if anyone can enlighten me!

First time looking through the KBB, and i see that in general chemistry, there are a ton of equations (just as i remembered!)! How much in depth do you need to memorize the equations and constants or are they provided somehow on the test?

In biology, the only real equation you seem to know is the allele frequency x^2 + 2xy + y^2 equation, or are there more that I am missing? Perhaps some Biochem henderson hasselbach?

For Organic chem, it does not seem like you need to remember any constants or equations except for the spectroscopy part. Do you need to remember all the absorption peaks?

Thanks to everyone ahead of time.

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[herkulease]

you should remember basic constants that get drilled into our heads. One thing that helps me is that if I used it over and over again then chances are I should know it.

So anyhow here's some things I think you should knnw. Universal Gas constant R. 8.31 J/K-mol or 0.821 L-atm

speed of light, Avogadro's number, Plank's constant perhaps. 6.62

Know conversions between temperatures. The combined gas law. specific heat. There's others I left out. I tend to remember when I get the problem thrown at me.

for IR, PMR, and NMR you shouldn't have to memorize the peak values. Just know a general range for them. I don't believe their are any professors who expect you to know exact values just general ranges. Like Alkanes are a little less than 3000. So the DAT isn't going to expect to know in detail what most teachers don't expect you to know either.

Just realize that there's only so much detail they can seriously ask you. They won't give you IR data and answer choice in which you will need a detailed chart of values to figure out the correct answer. It have a enough peaks in the general ranges to you can determine the answer

While we're on formulas and conversions. Might as well know your basic math formulas and conversions between ft, inches, miles, yards etc.

KBB has a pretty good set of formulas and constants you should know.

Don't worry too much about it being a lot. It seems that way but at this point you probably used it so many times I'm sure you know it just right now its being thrown at you all at once that you go OMG this is too much I can't remember all this.

 

[UndergradGuy7]

you should remember basic constants that get drilled into our heads. One thing that helps me is that if I used it over and over again then chances are I should know it.

So anyhow here's some things I think you should knnw. Universal Gas constant R. 8.31 J/K-mol or 0.821 L-atm

speed of light, Avogadro's number, Plank's constant perhaps. 6.62

Know conversions between temperatures. The combined gas law. specific heat. There's others I left out. I tend to remember when I get the problem thrown at me.

for IR, PMR, and NMR you shouldn't have to memorize the peak values. Just know a general range for them. I don't believe their are any professors who expect you to know exact values just general ranges. Like Alkanes are a little less than 3000. So the DAT isn't going to expect to know in detail what most teachers don't expect you to know either.

Just realize that there's only so much detail they can seriously ask you. They won't give you IR data and answer choice in which you will need a detailed chart of values to figure out the correct answer. It have a enough peaks in the general ranges to you can determine the answer

While we're on formulas and conversions. Might as well know your basic math formulas and conversions between ft, inches, miles, yards etc.

KBB has a pretty good set of formulas and constants you should know.

Don't worry too much about it being a lot. It seems that way but at this point you probably used it so many times I'm sure you know it just right now its being thrown at you all at once that you go OMG this is too much I can't remember all this.

Gas constant is 0.0821 L atm K-1 mol-1 minor typo.

For math remember miles to feet yards etc. Celsius to F etc. I think you covered most of the gen chem equations. Pretty much all you see on practice questions and kaplan for general chemistry.

For o-chem know the index of hydrogen deficiency too.

Math area formulas of triangle, trapezoid etc? I would memorize those and stuff too. Lots of math formulas.

 

[tommyngu]

how do they expect you to calculate things using those constants in chemistry such as Rydberg's constant? i know that they allow the use of the basic Windows calculator now, but do they really expect us to type in 0.00000000000000000218 ? is it required to memorize the units also or can we get by memorizing just the number and how to use it?

 

[Baylor2011]

You don't get a calculator during the GC part, so they won't ask you to do some ridiculous calculation. If they ask you to do a calculation, it should be something you can do either in your head or on the dry erase board.

 

[UndergradGuy7]

how do they expect you to calculate things using those constants in chemistry such as Rydberg's constant? i know that they allow the use of the basic Windows calculator now, but do they really expect us to type in 0.00000000000000000218 ? is it required to memorize the units also or can we get by memorizing just the number and how to use it?

Umm... scientific notation makes dividing or multiplying those kinds of numbers easier.

 

[tommyngu]

Umm... scientific notation makes dividing or multiplying those kinds of numbers easier.

I appreciate the smart reply... I understand that. What I was getting at was that there are many cases where the operations that include exponents and/or scientific notation can get unnecessarily time consuming since no calculator is provided as Baylor said. Who wants to go through all the adjustments and conversions to do a simple calculation? This isn't the math section.

 

[herkulease]

I appreciate the smart reply... I understand that. What I was getting at was that there are many cases where the operations that include exponents and/or scientific notation can get unnecessarily time consuming since no calculator is provided as Baylor said. Who wants to go through all the adjustments and conversions to do a simple calculation? This isn't the math section.

chances are if you get some obscure value that requires a calculator tthen will likely be just the correct setup.

for instance the problem wants you to solve for P in PV=nRT

Your answer will merely be nRT/V

with the correct values for each.

If in order to get moles you have to do 0.00001/25 then it'll be 0.00001/25(R)(T)/V

they'll provide several setups with some error. wrong R. wrong T(celsius instead of kelvin or wrong addition). etc.

I think you get the idea.

 

[tommyngu]

thanks for the useful info

 

[sonofastunna]

The short answer to this question is all. But not to worry, if you prepare by doing a lot of questions and mock exams, then you will pretty much remember all of them