A hydrocarbons `C_(4)H_(8)`, neither decolourised bromine in carbon tetrachloride nor reacted wiith HBr. When heated to 473 K with hydrogen in presence of a nickel catalyst, a new hydrocarbon, `C_(4)H_(10)`, was formed. What was the original hydrocarbon?

Explanation

The hydrocarbon can have the following isomers:

(A) and (B) are ruled out as the compound does not react with `Br_(2)` and HBr. Thus, the compound is cyclobutane. Cyclobutane on reduction opens up the ring and forms n-butane.