This question is about acids, bases and salts.
What is the pH of 1.80 dm31.80\text{ dm}^31.80 dm3 of 0.150 mol dm−30.150\text{ mol dm}^{-3}0.150 mol dm−3 of NaOH(aq)\text{NaOH(aq)}NaOH(aq) at 298 K298\text{ K}298 K?
[Kw=1.00×10−14 mol2 dm−6K_w = 1.00 \times 10^{-14}\text{ mol}^2\text{ dm}^{-6}Kw=1.00×10−14 mol2 dm−6 at 298 K298\text{ K}298 K]
Water is added to 25.0 cm325.0\text{ cm}^325.0 cm3 of 0.600 mol dm−30.600\text{ mol dm}^{-3}0.600 mol dm−3 HCl(aq)\text{HCl(aq)}HCl(aq) to produce 1000 cm31000\text{ cm}^31000 cm3 of diluted HCl(aq)\text{HCl(aq)}HCl(aq).
What is the pH of the diluted HCl(aq)\text{HCl(aq)}HCl(aq)? Give your answer to 2 decimal places.
A buffer solution has concentrations of 0.350 mol dm−30.350\text{ mol dm}^{-3}0.350 mol dm−3 CH3COOH(aq)\text{CH}_3\text{COOH(aq)}CH3COOH(aq) and 0.220 mol dm−30.220\text{ mol dm}^{-3}0.220 mol dm−3 CH3COONa(aq)\text{CH}_3\text{COONa(aq)}CH3COONa(aq).
KaK_aKa for CH3COOH=1.74×10−5 mol dm−3\text{CH}_3\text{COOH} = 1.74 \times 10^{-5}\text{ mol dm}^{-3}CH3COOH=1.74×10−5 mol dm−3 at 298 K298\text{ K}298 K.
What is the pH of the solution at 298 K298\text{ K}298 K? Give your answer to 2 decimal places.
A student is provided with hydrated copper(II) sulfate, CuSO4⋅5H2O\text{CuSO}_4 \cdot 5\text{H}_2\text{O}CuSO4⋅5H2O.
The student needs to prepare a standard solution of CuSO4⋅5H2O\text{CuSO}_4 \cdot 5\text{H}_2\text{O}CuSO4⋅5H2O with a concentration of 0.200 mol dm−30.200\text{ mol dm}^{-3}0.200 mol dm−3. Describe how the student would prepare 250.0 cm3250.0\text{ cm}^3250.0 cm3 of this solution, giving quantities, apparatus and method.
[Use molar masses: Cu=63.5 g mol−1\text{Cu} = 63.5\text{ g mol}^{-1}Cu=63.5 g mol−1, S=32.1 g mol−1\text{S} = 32.1\text{ g mol}^{-1}S=32.1 g mol−1, O=16.0 g mol−1\text{O} = 16.0\text{ g mol}^{-1}O=16.0 g mol−1, H=1.0 g mol−1\text{H} = 1.0\text{ g mol}^{-1}H=1.0 g mol−1]
