2. Acid-base chemistry

Question 1

Equilibrium constant

Answer 1

The concentration of products timesed/ concentration of reactants,
Only aqueous substances counted

Question 2

Acid dissociation constant and what effects it

Answer 2

When weak acid partially dissociates in water.
-temperature
-salt content (both go up together)
-local chemical environment

Question 3

Groups that are
-acidic (have resonance stabilization)
-basic (ability to accept proton)
-neither

Answer 3

-phenol (double ring+ -OH)
-amines (-NH2)
-amide(-O=C-NH2) bonds stabilised by resonance stabilisationand alcohol

Question 4

Rotation of bonds

Answer 4

Most single bonds: free rotation
Double/ triple: highly restricted rotation as distribution of e’ would be affected

Question 5

Why is alochol neither basic or acidic?

Answer 5

Because alocohol does not have resonance stabilisation nor the ability to accept a proton

Question 6

When pKa is on a Henderson-Hasselbalch graph:

Answer 6

Below pKa=protonated form
Above pKa=deprotonated form

Question 7

How do buffer solutions work?

Answer 7

Added substances react with the abundance of weak acid or conjugate base, resiting a change in pH