Question

what is the action of concentrated h2so4 on Br​

Answer 1

Answer:

The bromide ions are strong enough reducing agents to reduce the concentrated sulphuric acid. In the process the bromide ions are oxidised to bromine.

The bromide ions reduce the sulphuric acid to sulphur dioxide gas. This is a decrease of oxidation state of the sulphur from +6 in the sulphuric acid to +4 in the sulphur dioxide.

You can combine these two half-equations to give the overall ionic equation for the reaction:

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