A student is given an unknown organic compound and tests it with bromine water. The bromine water is decolourised rapidly at room temperature without UV light. Which homologous series does the compound most likely belong to?

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Question

A student is given an unknown organic compound and tests it with bromine water. The bromine water is decolourised rapidly at room temperature without UV light. Which homologous series does the compound most likely belong to?

Accepted Answer

C. Alkenes — Alkenes decolourise bromine water rapidly at room temperature through an electrophilic addition reaction across the C=C double bond. Alkanes only react with bromine under UV light (substitution), while alcohols and carboxylic acids do not decolourise bromine water in this way.

Answer

D. Carboxylic acids

Answer

A. Alkanes

Answer

B. Alcohols

Answer

C. Alkenes

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