Identify free radical inhibitor from following. (A) (B) \(\text{O}_{2}\) (C) (D) \(\text{CrO}_{3}\) Choose the correct answer from the options given below.
Show Hint
A free radical inhibitor traps chain-carrying radicals and converts them into stable, unreactive species.
Step 1: Understanding the Concept
A free radical inhibitor reacts with reactive radicals and forms stable radicals, so the chain reaction stops.
Step 2: Check each species
(A) p-Benzoquinone adds radicals to give a resonance-stabilised radical that cannot continue the chain, so it is an inhibitor.
(B) \(\text{O}_2\) is a diradical. It combines with alkyl radicals to give much less reactive peroxy radicals, so it also inhibits.
Step 3: Others
(C) Benzene is a stable aromatic compound that does not trap radicals. (D) \(\text{CrO}_3\) is only an oxidising agent. So only (A) and (B) are inhibitors.
Final Answer:
Only (A) and (B) are free radical inhibitors, which is option (D).
\[ \boxed{\text{(D) }\text{(A) and (B) Only}} \]
