If the pH of a solution is 10 and the concentration of protons is increased 10 fold by the addition of acid what is the new concentration of protons?

Question

a. 10^-10 M

b. 10^-11 M

c. 10^-9 M

d. 1 M

e. none of the above

Answer 1

Protons = H⁺

pH = -log [H⁺]

If pH = 10, [H⁺] = 10^-10 M

If increase [H⁺] 10 x, the new [H⁺] = 10^-10 x 10 = 10^-9 ANSWER (C)