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Bromine water alkene test
Compound A has an alkene functional group and an ester functional group.
Describe what will be seen when compound A is shaken with bromine water.
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Marking points
- 1 Gives an accepted initial bromine-water colour: orange, yellow or brown.
- 2 States that the bromine water turns colourless/is decolourised.
Full-mark answer
The orange bromine water is decolourised and turns colourless.
Why this answer loses marks
A precipitate forms when the compound is shaken with bromine water.
The required observation is a colour change in the bromine water, not formation of a precipitate.