Hydrocarbons having the same formula but variations in structure are called isomers.
a. true
b. false

The given statement is true.

Explanation:

Isomers are defined as two or more compounds with same structural formula but different arrangement of atom and chemical properties.

For example: Butane, 2-methyl propane are isomers with structural formula , acetone and propanal both isomers to each other with same structural formula of .

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