Which change causes the pH of 10 cm3 of 1.0×10−2 mol dm−3 HCl1.0 \times 10^{-2}\text{ mol dm}^{-3}\text{ HCl}1.0×10−2 mol dm−3 HCl to be doubled at 298 K? (Take Kw=1.0×10−14K_{\text{w}} = 1.0 \times 10^{-14}Kw=1.0×10−14 at 298 K)
adding 90 cm390\text{ cm}^390 cm3 of water
adding 990 cm3990\text{ cm}^3990 cm3 of water
adding 10 cm310\text{ cm}^310 cm3 of 1.0×10−2 mol dm−3 NaOH1.0 \times 10^{-2}\text{ mol dm}^{-3}\text{ NaOH}1.0×10−2 mol dm−3 NaOH
adding 10 cm310\text{ cm}^310 cm3 of 1.0×10−2 mol dm−3 HCl1.0 \times 10^{-2}\text{ mol dm}^{-3}\text{ HCl}1.0×10−2 mol dm−3 HCl
77 exam-style questions on AQA A Level Chemistry Acids and bases (A-level only), covering Brønsted–Lowry acid–base equilibria in aqueous solution (A-level only), Definition and determination of pH (A-level only), The ionic product of water, $K_w$ (A-level only), Weak acids and bases $K_a$ for weak acids (A-level only), pH curves, titrations and indicators (A-level only), and Buffer action (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.