How many and what are the isomers of #C_4H_8#?
A formula of
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,
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