12.13 - Ionic Product of Water, Kw Flashcards
1
Q
What is the chemical equation for the self-ionisation of water?
A
H2O(l) H+(aq) + OH-(aq)
2
Q
If you apply the equilibrium law to this, what is the result?
A
([H+][OH-])/[H2O] = A constant
3
Q
At given room temperature and pressure, what is the value of [H20]?
A
A constant
4
Q
Thus, what does the equation simplify to?
A
[H+][OH-] = A constant
5
Q
What is this constant called?
A
Kw, the ionic product of water
6
Q
What is its value at 298K?
A
1.00 x 10^-14 mol^2 dm^-6
7
Q
What is the relationship between pKw and Kw?
A
pKw = -log(Kw)
8
Q
As the temperature of water increases, what happens to Kw and pKw respectively?
A
Kw increases; pKw decreases
