Question

Chloroform is oxidised in the presence of sunlight to form

• A. \( CCl_4 \)
• B. \( COCl_2 \)
• C. \( CH_2Cl_2 \)
• D. \( CHCl_3 \)

Hint:

Chloroform + air + light gives a toxic gas; think phosgene.

Answer 1

The Correct Option is B

Step 1: Identify the reaction type: oxidation of \(CHCl_3\) by \(O_2\) under light, not chlorination or reduction, so options like \(CCl_4\) or \(CH_2Cl_2\) are ruled out.
Step 2: Oxidation replaces the C-H bond and one C-Cl arrangement with a C=O group, converting \(CHCl_3\) into an acyl chloride of carbonic acid.
Step 3: That compound is phosgene, \(COCl_2\), formed along with \(HCl\): \(2CHCl_3 + O_2 \rightarrow 2COCl_2 + 2HCl\).
Step 4: Therefore the sunlight oxidation product of chloroform is \(COCl_2\) (phosgene).