The balanced chemical equation for the reaction between magnesium and hydrochloric acid is:
Mg+2HCl→MgCl2+H2\text{Mg} + 2\text{HCl} \rightarrow \text{MgCl}_2 + \text{H}_2Mg+2HCl→MgCl2+H2
In an experiment, a student reacts 0.3 mol0.3\text{ mol}0.3 mol of magnesium, Mg\text{Mg}Mg, with 0.4 mol0.4\text{ mol}0.4 mol of dilute hydrochloric acid, HCl\text{HCl}HCl.
Use the equation to show that the magnesium is in excess.
Practise OCR GCSE Chemistry Introducing chemical reactions with exam-style questions for Foundation and Higher tier. 61 questions, matched to the OCR GCSE Chemistry (J248) specification and written in Paper 1 and Paper 2 (Foundation Tier) or Paper 3 and Paper 4 (Higher Tier) style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.