Chapter 9.5, Problem 9.12PP

Calculate the value of ${\text{[OH}}^{\text{-}}\text{]}$ from the given ${\text{[H}}_3{\text{O}}^{\text{+}}\text{]}$ in each solution and label the solution asacidic or basic:
${\text{(a) [H}}_{\text{3}}{\text{O}}^{\text{+}}{\text{] = 10}}^{\text{-3}}{\text{M; (b) [H}}_{\text{3}}{\text{O}}^{\text{+}}{\text{] = 10}}^{\text{-11}}{\text{M; (c) [H}}_{\text{3}}{\text{O}}^{\text{+}}\text{] = 2}{\text{.8×10}}^{-10}{\text{M; (d) [H}}_{\text{3}}{\text{O}}^{\text{+}}\text{] = 5}{\text{.6×10}}^{-4}\text{M}\text{. }$