How many and what are the isomers of C4H8?

1 Answer
Feb 20, 2016

A formula of C4H8 specifies 1 degree of unsaturation.

Explanation:

One degree of unsaturation involves the presence of an unsaturated bond OR a ring.

So I can count 5 structural isomers: 2 rings, and 3 olefins. One of the olefins has 2 geometric isomers.

As regards the degree of unsaturation, this is a useful reference when we compare the formula to a saturated molecule, CnH2n+2, i.e. butane if n = 4. How many isomers can butane, C4H10, generate?

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