Which test shows that a hydrocarbon is unsaturated?
Answer and explanation
Correct answer: A. It decolourises bromine water
Alkenes add bromine across the double bond, so orange bromine water turns colourless.
Answer: It decolourises bromine water.
Why not the others: It burns with a blue flame: saturated hydrocarbons can burn with a blue flame. It turns litmus red: hydrocarbons are neutral. It dissolves in water: hydrocarbons are insoluble.
Answer: It decolourises bromine water.
Why not the others: It burns with a blue flame: saturated hydrocarbons can burn with a blue flame. It turns litmus red: hydrocarbons are neutral. It dissolves in water: hydrocarbons are insoluble.
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