20.2 The pH Scale and Strong Acids Flashcards
1
Q
When the pH is above 7
A
Acidity
2
Q
When the pH is below 7
A
Alkalinity
3
Q
When the pH is 7
A
Neutral
4
Q
What is the qualitative way of determining pH?
A
Using (pH indicator paper or universal indicator solution) - cheaper and less accurate // or pH meters.
5
Q
What is the quantitative way of determining pH?
A
pH = -log[H+] [H+] = 10^-pH
6
Q
What is pH?
A
A measure of activity of a solution and is used to calculate its hydrogen ion concentration.
7
Q
Why do we use pH?
A
The concentration of Hydrogen ions vary massively over solutions
~Between 2-3 mol dm^-3 to 1x10^-20
8
Q
Approximations for the pH of Strong Acids
A
HA(aq) –> H+(aq) + A-(aq)
So
[H+(aq)] = [HA(aq)]
