MDCAT ECAT Chemistry MCQs

Correct answer B. 6 times the original

Correct answer D. 2 times the original

Correct answer C. Tertiary > secondary > primary > methyl

Correct answer C. Polar protic, such as water

Correct answer A. Ethanol

Correct answer A. Concentrated alcoholic KOH and a high temperature

Correct answer B. The base removes a β-hydrogen as the C–X bond breaks, in a single step

Correct answer D. first order, proceeding via a carbocation intermediate

Correct answer B. But-2-ene

Correct answer B. 6

Correct answer B. BF₃

Correct answer B. its π bond is weaker than a σ bond and its electrons are exposed to electrophiles

Correct answer B. Ethene

Correct answer D. 2-Methylbut-2-ene

Correct answer B. 2-Bromopropane

Correct answer B. 32 g

Correct answer C. between a C–C single bond (154 pm) and a C=C double bond (134 pm)

Correct answer B. 6

Correct answer C. Substitution keeps the stable delocalised π system intact, whereas addition would destroy it

Correct answer C. NO₂⁺