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Question
Give a balanced equation for a reaction involving the evolution of gas on the addition of dilute acid to sodium sulphite.
Solution
Sodium sulphite when reacting with dil. `"H"_2"SO"_4` evolves gas `"SO"_2`.
\[\ce{Na2SO3 + H2SO4 [dil.]->Na2SO4 + H2O + SO2 (g)}\]
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