Buffers Flashcards
1
Q
What is the exam definition for a buffer?
A
A solution that minimizes pH changes on addition of small amounts of acid and alkali?
2
Q
What makes up a buffer?
A
A weak acid and its salt
e.g. ethanoic acid and sodium ethanoate
3
Q
What are the 2 methods for making a buffer?
A
Mix a weak acid with its salt
and
Mix excess weak acid with a strong alkali
4
Q
How does a buffer work?
A
Relies of Le Chatelier’s principle.
Will either use up A- or HA to ensure the H+ concentration change is minimized
5
Q
What equations do we use to calculate buffer pHs?
A
ka = [H+][A-]/[HA]
Followed by pH = -log [H+]
6
Q
If [HA] and [A-] are the same then pH = ?
A
pKa
7
Q
What are some common buffer examples in real world?
A
Blood
Acidosis
Kidneys
Cells
Shampoo
Biological Washing Powder
Food
The Ocean
8
Q
A
