Answer:
(c) Bromine is heavier than air.
Explanation:
When a gas jar full of air is placed upside down on a gas jar full of bromine vapours, the red-brown vapours of bromine from the lower jar go upward into the jar containing air. In this experiment , Bromine vapour (or bromine gas) is red-brown in colour, and it is heavier than air ; therefore it is settling in bottom of appratus and air is rising at the top of apparatus.
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