An environmental chemist is testing a dry soil-crust sample, S, suspected of being contaminated with sulfate ions. The chemist adds a few drops of barium chloride solution directly onto the dry, solid sample.
Explain why this test fails to identify the sulfate ions, and describe how the chemist should modify the procedure to obtain a valid test result.
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.
