Concentrated acidified potassium dichromate, K2Cr2O7 [K2Cr2O7/H2SO4 (conc.)] is the oxidising agent used for conversion of ethanol to ethanoic acid.

(i) Litmus test will be given by ethanoic acid. It will turn the blue litmus solution red whereas in ethanol no such colour change is observed.

(ii) Ethanoic acid will react with sodium carbonate and a brisk effervescence owing to formation of carbon dioxide will be observed.2CH3COOH + Na2CO3 → 2CH3COONa + H2O + CO2
On the other hand ethanol will not react with sodium carbonate.
C2H5OH + Na2CO3 → No reaction
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