Ionic product of water, Kw

Calculate the pH of a 0.125 mol dm$^{-3}$ solution of sodium hydroxide.

Which solution has a pH of 11.0 at 298 K? A. $10^{-3}\ \mathrm{mol\,dm^{-3}}$ $\ce{KOH(aq)}$ B. $10^{-11}\ \mathrm{mol\,dm^{-3}}$ $\ce{KOH(aq)}$ C. $10^{-3}\ \mathrm{mol\,dm^{-3}}$ $\ce{NH3(aq)}$ D. $10^{-3}\ \mathrm{mol\,dm^{-3}}$ $\ce{HCl(aq)}$

Which of these solutions has a pH greater than 7 at 25 °C? A. $[\ce{H+}] = 1.0 \times 10^{-5}\ \mathrm{mol\,dm^{-3}}$ B. $[\ce{OH-}] = 1.0 \times 10^{-10}\ \mathrm{mol\,dm^{-3}}$ C. $[\ce{H3O+}] = 1.0 \times 10^{-11}\ \mathrm{mol\,dm^{-3}}$ D.…

Nitric acid is a strong acid manufactured on a large scale. A pH probe is immersed in a small volume of $0.010\ \mathrm{mol\,dm^{-3}}$ nitric acid. The pH is recorded while distilled water is added to the acid at a steady rate and at constant temperature. (i)…