Dehydration of but-2-ol via E1 mechanism

Steps:

• But-2-ol (CH3CH(OH)CH2CH3) protonates with H2SO4, loses water to form secondary carbocation at C2.
• Carbocation eliminates H+ from adjacent beta-carbons (C1 or C3).
• Elimination from C1 (CH3 group) yields but-1-ene: CH3CH2CH=CH2.
• Elimination from C3 (CH2 group) yields but-2-ene: CH3CH=CHCH3.

Why B is correct:

• Products match Zaitsev's rule, favoring more substituted alkene (but-2-ene) alongside minor but-1-ene from beta-elimination.

Why the others are wrong:

• A: Lists propene (CH3CH=CH2), requiring invalid C-C bond cleavage.
• C: Identical to A, includes incorrect propene.
• D: Includes butane (CH3CH2CH3), an alkane not formed in dehydration.

Final answer: B