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COMEDK2018ChemistryThermodynamics (C)

Which cycloalkane has the lowest heat of combustion per CH ₂ group?

Options

  1. Acyclopropane
  2. Bcyclobutane
  3. Ccyclopentane
  4. Dcyclohexane

Correct answer

D. cyclohexane

Step-by-step solution

Cyclohexane has the lowest heat of combustion per CH ₂ group. As, stability increase upto 6 membered ring due to decrease in angular strain. Also heat of combustion is measure for chemical stability.

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