JEE Main · 2026 · 24 Jan 2026 · Shift 1 · Hydrocarbons

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Arrange the following alkenes in decreasing order of stability.
I. (see structure)
II. (see structure)
III. (see structure)
IV. (see structure)

Choose the correct answer from the options given below :

(A)III $>$ I $>$ II $>$ IV
(B)III $>$ II $>$ I $>$ IV
(C)I $>$ III $>$ II $>$ IV✓ Correct
(D)I $>$ III $>$ IV $>$ II

Answer: (C)

Solution

Alkene stability rises with the number of alkyl groups on the double bond through hyperconjugation and the inductive effect, and for a given substitution a trans isomer is more stable than its cis counterpart. Structure I is tetrasubstituted, III is trisubstituted, II is the trans-disubstituted alkene and IV is the cis-disubstituted alkene. The decreasing order of stability is

I > III > II > IV

JEE Main · 2026 · 24 Jan 2026 · Shift 1 · Single correct option

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