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Actually, in a book I found that 2-methylpropene is more stable than trans-but-2-ene. But, my teacher and also I am convinced that trans-but-2-ene is more stable than 2-methylpropene. My reasoning is that 2-methylpropene is less stable due to the steric repulsion of the -CH3 on one sp2 hybridised carbon. Also, 2-methylpropene is more reactive for the electrophilic addition reactions involving carbocation intermediate as a 3° carbocation will form and in case of trans-but-2-ene, a 2° carbocation is formed. Please say if I am correct and if not, please explain the correct comparative analysis.