This is a matching answer type question as classified in NCERT Exemplar
Correct option is (i)
CCl3NO2 stands for chloropicrin, which is known as tear gas. Cl is the element of the highest electron gain enthalpy. Sulphur is the element belonging to 16th group, also known as chalcogens.
The inertness of ? subshell electrons towards bond formation is known as inert pair effect. This effect increases down the group thus, for Sn, oxidation state is more stable, whereas, for Pb, oxidation state is more stable, i.e., is reducing while is oxidising.
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