A solution is prepared that is 0.20 M in Na2CO3 and 0.10 M in NaHCO3. Given pK_a2(H2CO3) = 10.33 and log 2 = 0.301, its pH is

JEE Main levelSingle correct optionDifficulty 2 of 3ia198

A solution is prepared that is $0.20 M$ in $Na X_{2} CO X_{3}$ and $0.10 M$ in $NaHCO X_{3}$ . Given $p K_{a 2} (H X_{2} CO X_{3}) = 10.33$ and $lo g 2 = 0.301$ , its pH is

This is a

CO X_{3} X^{2 -} / HCO X_{3} X^{-}

buffer:

pH = p K_{a 2} + lo g (0.20/0.10) = 10.33 + 0.301 = 10.63

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