8. Kw is not constant with respect to temperature, but rather decreases as the temperature of the water decreases. At 10oC, Kw = 3.0 x 10-15. What is the pH of pure water at 10oC?
First, we need to substitute into the Kw expression. Given

H2O (l) H+ (aq) + OH- (aq) ,

what is the relationship between [ H+ ] , [ OH- ] and [ H2O ] ?

a) [ H+ ] = [ H2O ]
b) [ H+ ] = [ OH- ]
c) [ H+ ] = [ H2O ] - [ OH- ]
d) relationship cannot be determined at this temperature