A hydrocarbon, C4H6 absorbs two moles of hydrogen in the presence of platinum as catalyst.?

When 1 mole C₄H₆ reacts with 2 moles of H₂ gas, 4 moles of H atoms are added and then the hydrocarbon becomes C₄H₁₀. C₄H₁₀ is the molecular formula of a saturated straight-chained alkane, which is inert towards bromine and potassium permanganate. It can be deduced that C₄H₆ would have 2 C=C double bonds or 1 C≡C triple bond.

Hence, there are 4 possible structures for C₄H₆.

(If alkynes are out of the syllabus, neglect the last two structures.)

yep

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