# Buffer Solutions

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• Created by: J.E.C.
• Created on: 01-05-14 17:04
What is a buffer solution?
A solution which can resist changes in pH despite the addition of acid or alkali.
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Buffer solutions are usually made of...?
Weak acid and one of its salts or a weak base and one of its salts
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The action of a buffer depends on the equilibrium of the weak acid which is written as...?
HA (aq) --> H+ (aq) + A- (aq)
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EWhat two assumptions can we make based on this equation?
1. All the A- ions come from the salt 2. Almost all the HA molecules put into the buffer remain unchanged - if some acid is added the A- ions react with the extra H+ to give HA and water. If alkali is added the H+ ions lost - regenerated by acid
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Ka =
[H+ (aq)] x ([salt] / [acid])
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The pH of the buffer solutio depends on what two factors...?
1. Value of Ka 2. Ratio of salt:acid
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## Other cards in this set

### Card 2

#### Front

Buffer solutions are usually made of...?

#### Back

Weak acid and one of its salts or a weak base and one of its salts

### Card 3

#### Front

The action of a buffer depends on the equilibrium of the weak acid which is written as...?

### Card 4

#### Front

EWhat two assumptions can we make based on this equation?

Ka =