A technician is testing an unknown fertilizer suspected to contain ammonium sulfate, (NH4)2SO4(\text{NH}_4)_2\text{SO}_4(NH4)2SO4. They warm a sample of the fertilizer with aqueous sodium hydroxide in a boiling tube, which releases a pungent gas.
To identify this gas, the technician holds a piece of damp red litmus paper near the mouth of the tube.
State the colour change that would be observed on the damp red litmus paper.
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.
