Question

Which step is chain propagation step in the

following mechanism?

(i) $Cl_{2}\overset{\quad h\upsilon\quad}{\rightarrow}Cl^{\bullet} + Cl^{\bullet}$

(ii) $Cl^{\bullet} + CH_{4} \rightarrow^{\bullet}CH_{3} + HCl$

(iii)$Cl^{\bullet} + Cl^{\bullet} \rightarrow Cl_{2}$

(iv)$\bullet CH_{3} +^{\bullet}Cl \rightarrow CH_{3}Cl$

• A. (i)
• B. (ii)
• C. (iii)
• D. (iv)

Answer 1

Answer: (B)

(ii)

Answer 2

: Chain propagating step is

$Cl^{{^\circ}} + CH_{4} \rightarrow^{\bullet}CH_{3} + HCl$