Chemistry - GOC Question with Solution | TestHub

Concept: Carbocation stability order

3° > 2° > 1° > CH₃⁺

CH₃–CH₂⁺ (ethyl carbocation) is a primary carbocation.

(a) (CH₃)₃C⁺ → tertiary → more stable

(b) CH₃–CH⁺–CH₃ → secondary → more stable

(c) CH₃–CH₂–CH₂⁺ → primary but less stable than ethyl carbocation (fewer hyper conjugative structures)

(d) CH₃⁺ → least stable

Therefore, A, B, and C are correct.