Chemistry · Oct / Nov 2023 · Paper 11 · Question 40

A student does two experiments. In experiment 1, ammonium carbonate is reacted with dilute hydrochloric acid. In experiment 2, ammonium carbonate is heated with aqueous sodium hydroxide. In each experiment, the gas evolved is tested with damp blue litmus paper and damp red litmus paper. Which row correctly shows the colour of both pieces of litmus paper at the end of each experiment?

1. Aexperiment 1: blue, experiment 2: blue
2. Bexperiment 1: blue, experiment 2: red
3. Cexperiment 1: red, experiment 2: blue
4. Dexperiment 1: red, experiment 2: red

As printed in the paper