Which is more stable: cyclobutane or cycloheptane?

[AMan24]

Homework Statement

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Which is more stable cyclobutane or cycloheptane?

Homework Equations

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[(n-2)180)]/n = angle

The Attempt at a Solution

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So the closer the angle is to 109.5 the more stable (except for cyclopentane vs cyclohexane).
n = number of carbons

[(7-2)180)]/7 = 128.57, 128.57 - 109.5 = 19.07

[(4-2)180)]/4 = 90, 109.5 - 90 = 19.5

cycloheptane is closer to 109.5 so its more stable?

 

[mjc123]

Are cyclobutane and cycloheptane planar?