Gas formed when chloroform (trichloromethane) is oxidised by air and light

The same question, asked 2 times: 12 May 2024 S2, 11 Apr 2026 S2. Every wording below, oldest first.

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Question 1
12 May 2024 S2
62 $Which of the following gases is formed during oxidation of trichloromethane?$
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Question 2
11 Apr 2026 S2
38 $Which of the following compounds is formed when chloroform is exposed to air and light?$
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