An analyst is determining the concentration of a waste lithium hydroxide solution, LiOH\text{LiOH}LiOH, from a battery-recycling process.
During a titration, 25.0 cm3 of this lithium hydroxide solution is neutralised by a 0.125 mol dm-3 solution of phosphoric acid, H3PO4\text{H}_3\text{PO}_4H3PO4.
3LiOH+H3PO4→Li3PO4+3H2O 3\text{LiOH} + \text{H}_3\text{PO}_4 \rightarrow \text{Li}_3\text{PO}_4 + 3\text{H}_2\text{O} 3LiOH+H3PO4→Li3PO4+3H2OIt is found that 22.40 cm3 of the phosphoric acid solution is required to completely neutralise the 25.0 cm3 of lithium hydroxide solution.
Calculate the concentration of the lithium hydroxide solution in mol dm−3\text{mol dm}^{-3}mol dm−3.
157 exam-style questions on Edexcel GCSE Chemistry 6.2 Quantitative analysis, covering 6.2.1 Concentration in mol dm⁻³ and titration calculations, 6.2.2 Percentage yield and why actual yield falls short, 6.2.3 Atom economy of a reaction, 6.2.4 Choosing a reaction pathway, and 6.2.5 Molar volume of gases and Avogadro's law. Each one has a worked solution and a mark scheme showing where the marks go.