Take the first ionisation of H2SO4 as complete and K_a2 = 1.2x10^-2 for HSO4-. Select the correct statement(s).

The pH of 0.050 M H2SO4 is about 1.23

The pH of 0.10 M NaHSO4 is about 1.54

In 0.10 M H2SO4, [SO4^2-] is about 0.0098 M

The pH of 0.10 M H2SO4 is exactly 1.00 because both protons ionise completely

The pH of 0.050 M H2SO4 is about 1.23

The pH of 0.10 M NaHSO4 is about 1.54

In 0.10 M H2SO4, [SO4^2-] is about 0.0098 M

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ia205

Take the first ionisation of $H X_{2} SO X_{4}$ as complete and $K_{a 2} = 1.2 \times 1 0^{- 2}$ for $HSO X_{4} X^{-}$ . Select the correct statement(s).

AThe pH of $0.10 M$ $H X_{2} SO X_{4}$ is exactly $1.00$ because both protons ionise completely
BThe pH of $0.050 M$ $H X_{2} SO X_{4}$ is about $1.23$
CThe pH of $0.10 M$ $NaHSO X_{4}$ is about $1.54$
DIn $0.10 M$ $H X_{2} SO X_{4}$ , $[SO X_{4} X^{2 -}]$ is about $0.0098 M$

NaHSO X_{4}

x^{2} / (0.10 - x) = 0.012

gives

x = 0.0292

, pH

1.54

. For

0.050 M

H X_{2} SO X_{4}

x^{2} + 0.062 x - 0.0006 = 0

gives

x = 0.00851

[H X^{+}] = 0.0585

, pH

1.23

. For

0.10 M

x = 0.0098 M = [SO X_{4} X^{2 -}]

and pH

= 0.96

, not

1.00