0653.C12.4.03 — Describe tests to identify the gases: (a) . ammonia, NH3, using damp red litmus paper (b) . carbon dioxide, CO2, using limewater (c) . chlor: past paper questions
Real questions on 0653.c12.4.03 — describe tests to identify the gases: (a) . ammonia, nh3, using damp red litmus paper (b) . carbon dioxide, co2, using limewater (c) . chlor
The newest 13 of 13 written questions. Open one to see it on the real paper.
- 0653/32 · October/November 2025 · Q6b(ii)[2]
A gas is produced during the reaction. Describe a test to identify the gas. Give the observation for a positive result. test
See it on the paper → - 0653/33 · October/November 2025 · Q6b(ii)[2]
A gas is produced during the reaction. Describe a test to identify the gas. Give the observation for a positive result. test
See it on the paper → - 0653/32 · May/June 2025 · Q6b[1]
The oxygen is collected and tested. State the observation for the positive result. test Describe the test for oxygen gas.
See it on the paper → - 0653/63 · May/June 2024 · Q3d(iii)[1]
State the name of the gas formed in test 3.
See it on the paper → - 0653/63 · May/June 2024 · Q3d(iv)[1]
State the name of the cation (positive ion) present that causes the gas to be produced in test 3.
See it on the paper → - 0653/12 · October/November 2023 · Q7[1]
What can he use to test for carbon dioxide?
See it on the paper → - 0653/12 · October/November 2023 · Q21[1]
Which test is used to identify ammonia?
See it on the paper → - 0653/63 · October/November 2023 · Q3b(i)[1]
The limewater turns milky. State the name of the gas produced.
See it on the paper → - 0653/63 · October/November 2023 · Q3c(i)[1]
The damp red litmus paper turns blue. State the name of the gas produced.
See it on the paper → - 0653/33 · May/June 2023 · Q2c(iii)[2]
Describe a test for carbon dioxide and state the observation for a positive result. test observation
See it on the paper → - 0653/62 · May/June 2023 · Q3b(i)[1]
Describe the test to confirm that the gas made is carbon dioxide. Include the observation for a positive result. test observation
See it on the paper → - 0653/32 · February/March 2023 · Q2a(iii)[1]
Describe the test for hydrogen gas and state the observation for a positive result. test observation
See it on the paper → - 0653/11 · October/November 2022 · Q21[1]
Which pair of gases can be identified using damp litmus paper and limewater?
See it on the paper →
What examiners said
Generally, candidates found this question demanding. A minority knew that oxygen relights a glowing splint. It was clear that most of the remaining candidates were not familiar with the test. Inaccuracies included the test for hydrogen which results in a ‘pop’ sound, the test for carbon dioxide, and the use of a completely extinguished match or splint to relight, not a glowing one.
— Examiner report, May/June 2025, 0653/32 Q6(b) (Cambridge)
Most candidates knew that limewater is used to test for carbon dioxide.
— Examiner report, October/November 2023, 0653/12 Q7 (Cambridge)
Most candidates correctly stated that limewater turns milky with carbon dioxide.
— Examiner report, October/November 2023, 0653/63 Q3(b)(i) (Cambridge)
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