An agricultural chemist is testing a sample of runoff water suspected of being contaminated with sulfate-based fertilizers.
To test for the presence of sulfate ions (SO42−\text{SO}_4^{2-}SO42−), the chemist acidifies a 5.0 cm35.0\text{ cm}^35.0 cm3 sample of the runoff water with a few drops of dilute hydrochloric acid, before adding barium chloride solution (BaCl2\text{BaCl}_2BaCl2).
State the purpose of adding the dilute hydrochloric acid in this procedure.
Practise Edexcel GCSE Chemistry Qualitative analysis: tests for ions with exam-style questions for Foundation and Higher tier. 127 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.
