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Question
Give reasons for the following:
A piece of wood becomes black when concentrated sulphuric acid is poured on it.
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Solution
A piece of wood becomes black because carbon is set free when cellulose [C6H10O5]n gets charred by conc. H2SO4.
\[\ce{[C6H10O5]_n ->[conc. H2SO4] 6[C]_n + 5[H2O]_n}\]
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