Calculate the pH of a $0.10\text{M}$ solution of sodium hydroxide (NaOH). Give your answer correct to two decimal places.

Step-by-step solution

1. Sodium hydroxide is a strong base and dissociates completely: $\mathrm{NaOH}\to \mathrm{N}{\mathrm{a}}^{+}+\mathrm{O}{\mathrm{H}}^{-}$.
2. Therefore the concentration of hydroxide ions equals the molarity of the solution: $[O{H}^{-}]=0.10\text{M}$.
3. Calculate pOH using $pOH=-{\log }_{10}[O{H}^{-}]=-{\log }_{10}(0.10)=1.00$.
4. Use the relation $pH=14-pOH$ to obtain $pH=14-1.00=13.00$.

Concept tested: pH of strong bases

Published 22 August 2026 · How this solution was prepared and checked

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