A student investigated how the pH of dilute hydrochloric acid changes as magnesium oxide is added. Their results are shown in the graph in Figure 1.

Using Figure 1, give the mass of magnesium oxide required to make a neutral mixture.
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 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.