A hydrocarbon C5H10 does not react with chlorine in the dark but gives a single monochloro compound C5H9Cl in bright sunlight. Identify the hydrocarbon.
A hydrocarbon C5H10 does not react with chlorine in the dark but gives a single monochloro compound C5H9Cl in bright sunlight. Identify the hydrocarbon.
Solution and Explanation
A hydrocarbon with the molecular formula, C5H10 belongs to the group with a general molecular formula CnH2n. Therefore, it may either be an alkene or a cycloalkane. Since hydrocarbon does not react with chlorine in the dark, it cannot be an alkene. Thus, it should be a cycloalkane. Further, the hydrocarbon gives a single monochloro compound, C5H9Cl by reacting with chlorine in bright sunlight. Since a single monochloride mixture is formed, the hydrocarbon must contain all equivalent H-atoms. Also, as all H−atoms of a cycloalkane are identical, the hydrocarbon must be a cycloalkane. Hence, the said compound is cyclopentane.
The reactions involved in the question are:
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