Which of the following compounds would react with bromine water at room temperature?
Show the answer and explanation
Correct answer
B. Ethene
Principle or equation
Alkenes (containing a C=C double bond) undergo addition reactions with bromine water, decolorizing it. Alkanes, alcohols, and haloalkanes do not react under these conditions.
Why this answer is correct
Ethene (C2H4) has a double bond and reacts with bromine water, adding Br2 across the double bond and decolorizing the orange/brown solution. Ethane (alkane), ethanol (alcohol), and chloroethane (haloalkane) are saturated or lack the reactive double bond.
Example
Propene also decolorizes bromine water, while propane does not.
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