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NEET levelSingle correct optionDifficulty 1 of 3sb168

An aqueous solution of sodium carbonate is alkaline because

Athe carbonate ion is hydrolysed to give $OH X^{-}$
Bsodium carbonate reacts with water to give $NaOH$ and $O X_{2}$
Ccarbonate ion donates a proton to water to give $CO X_{2}$
Dthe sodium ion is hydrolysed to give $OH X^{-}$

Answer: A

Na X^{+}

is the cation of a strong base and is not hydrolysed.

CO X_{3} X^{2 -}

is the conjugate base of the weak acid

HCO X_{3} X^{-}

and takes a proton from water:

CO X_{3} X^{2 -} + H X_{2} O HCO X_{3} X^{-} + OH X^{-}

, so the solution is alkaline.

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