Two orgo conceptual questions

[299678]

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Anyone can explain this?
Q1. a neutral acid has a ka = 1.2 x 10^-5. when the pH =9, the acid exists mainly as?
a) anion
b) zwitterion
c) cation
d) a neutral compound
e) amphoteric oxide

Q2. Consider acetic acid, pKa = 4.34. When pH = 2, which is present?
a) acetate ion
b) protonated acid
c) neutral acid
d) zwitterion

 

[azar87]

Anyone can explain this?
Q1. a neutral acid has a ka = 1.2 x 10^-5. when the pH =9, the acid exists mainly as?
a) anion
b) zwitterion
c) cation
d) a neutral compound
e) amphoteric oxide

Q2. Consider acetic acid, pKa = 4.34. When pH = 2, which is present?
a) acetate ion
b) protonated acid
c) neutral acid
d) zwitterion

I am not sure about question 1 cuz it says neutral acid made me beleive it was a zwitterion ........question 2 i would say protonated acid because it is in such a low pH that the H+ will be the most accumulated ie protonated. question 1 i would say anion because it has lost its H+ and the species is negativley charged

 

[Moabmad]

Q1. I would say based on the pka (11.3) compared to the pH of 9 that the acid would be in its protonated state and hence be a neutral compound - answer D

Q2. Again, based on the comparison of pka to pH, the acid will remain in its protonated state - answer B.

 

[299678]

Anyone can explain this?
Q1. a neutral acid has a ka = 1.2 x 10^-5. when the pH =9, the acid exists mainly as?
a) anion
b) zwitterion
c) cation
d) a neutral compound
e) amphoteric oxide

Q2. Consider acetic acid, pKa = 4.34. When pH = 2, which is present?
a) acetate ion
b) protonated acid
c) neutral acid
d) zwitterion

the correct answer is 1, anion 2. c
I don't really understand the reasoning from destroyer

 

[loveoforganic]

The pKa of the first compound is around 5, not 11, so anion is right using the reverse logic of that posted.

 

[prsndwg]

nvm

 

[hausee]

is a tetrad at prophase I considered one chromosomes with 4 chromotids??

two chromosome with 4 chromotids. They are not physically linked. While after metaphase II, it separated and produced two non-linked chromosomes(before separation they been called chromotid )