When citric acid crystals are dissolved in water, a solution forms.
Blue litmus paper dipped in this solution turns red.
State the ion present in this solution that causes the litmus paper to turn red.
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 276 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.
