Physical Chemistry- Acids, Bases and Kw Flashcards
1
Q
Define an acid
A
A proton donor
2
Q
Define a base
A
A proton acceptor
3
Q
Define a strong acid
A
An acid that completely dissociates in solution to release H+ ions
4
Q
Define a strong base
A
A base that completely dissociates in solution to release OH- ions
5
Q
Define pH
A
-log[H+]
6
Q
[H+] formula
A
10-pH
7
Q
What is the acid dissociation constant for weak acids?
A
Ka=[H+][A-]/[HA]
8
Q
What are the units of Ka?
A
moldm-3
9
Q
What is Ka a measure of?
A
A quantitative measure of how strong a weak acid is
10
Q
pKa formula
A
-logKa
11
Q
How to calculate pH of a weak acid?
A
Ka=[H+]2/[HA]
Find [H+]
Use -log[H+]
12
Q
Define Kw
A
Kw= [H+][OH-]
13
Q
What is the effect of temperature on Kw?
A
Dissociation of water is endothermic
So equilibrium will shift to the to the right
So Kw will increase and therefore [H+] will increase so pH will decrease
14
Q
A
