Question

Slow oxidation of chloroform in air leads to the formation of:
a.) Formyl chloride
b.) Formic acid
c.) $COC{{l}_{2}}$
d.) Trichloro acetic acid

Answer 1

Hint: Slow oxidation of chlorine in presence of sunlight produces phosgene gas. This released gas was used in wars specially in world war 1.

Complete answer:
Trichloromethane is the chemical name of chloroform and it is chemically represented by $CHC{{l}_{3}}$.
When chloroform is allowed to oxidize in air slowly, it leads to the formation of carbonyl chloride $COC{{l}_{2}}$. Carbonyl chloride is a very poisonous gas whose common name is phosgene. It can have adverse effects on your skin, eyes, throat and lungs.
So in the presence of light chloroform that is also known as trichloro methane reacts with oxygen which results in the formation of carbonyl chloride $COC{{l}_{2}}$(phosgene) and $HCl$, hydrochloric acid.

Overall reaction is:
$CHC{{l}_{3}}+21{{O}_{2}}\xrightarrow{light}COC{{l}_{2}}+HCl$
So, the answer is $COC{{l}_{2}}$ produced on oxidation of chloroform in presence of light.

From all the above options option C is correct.

Note: Phosgene is one of the very toxic gases. In little amounts too is very harmful to humans. It is produced by the slow reaction of chloroform with oxygen in the presence of light. That is when chloroform is kept in open then phosgene gas is formed as it will have oxygen from the atmosphere and sunlight too.
It should be kept in proper containers in kerosene and petrol so that no oxygen is available for oxidation. For the manufacturing of certain chemicals and pesticides phosgene is commonly used. It is found in low lying areas because its density is higher than air. It is inflammable and can if contacted can produce symptoms like irritation in eyes, skin allergy, breathing problems, pulmonary edema etc.