Alkene reactions: identifying reduction and addition types

Steps:

• Examine the starting molecule: 3-methyl-1-butene is an alkene with a C=C bond.
• Analyze step ¹ Cl: this likely involves hydrogenation or catalytic reduction to saturate the double bond, forming an alkane intermediate.
• Identify the intermediate: the saturated hydrocarbon now lacks the reactive C=C.
• Analyze step ² with Cl: the alkane undergoes free radical chlorination, an electrophilic addition-like process at C-H bonds, adding Cl.

Why C is correct:

• Reduction converts the alkene to an alkane by adding H₂ (per hydrogenation definition), followed by electrophilic addition of Cl₂ across C-H in the radical mechanism.

Why the others are wrong:

• A: First step is not oxidation, as no O addition or bond breaking occurs.
• B: Second step is electrophilic, not nucleophilic, addition (Cl⁺ acts as electrophile).
• D: First step is reduction, not nucleophilic addition (no nucleophile like OH⁻ involved).

Final answer: C