Exercise 1 | The Properties of Acids and Bases

If Kw = 2.93 x 10-15 2  at 10°C, what is the pH of pure water at this temperature?

Kw = [H3O+][HO-]

Pure water: [H3O+] = [HO-]


Kw = [H3O+]2 = 2.93 x 10-15 2

 [H3O+] = 5.41 x 10-8 M

⇒ pH = -log [H3O+] = 7.27