Calculate [S2–] in a solution originally having 0.1 M – HCl and 0.2 M – H2S. For H2S, Ka1 = 1.4 × 10

Question

Calculate [S2–] in a solution originally having 0.1 M – HCl and 0.2 M – H2S. For H2S, Ka1 = 1.4 × 10−7 and Ka2 = 1.0 × 10−14.

Accepted Answer

$K_{a_{1}}:K_{a_{2}} = \frac{\left\lbrack H^{+} \right\rbrack^{2}\left\lbrack S^{2 -} \right\rbrack}{\left\lbrack H_{2}S \right\rbrack}$

Or, $\left( 1 \times 10^{- 7} \right) \times \left( 1.0 \times 10^{- 14} \right) = \frac{(0.1)^{2} \times \left\lbrack S^{- 2} \right\rbrack}{0.2} \Rightarrow \left\lbrack S^{2 -} \right\rbrack = 2.8 \times 10^{- 20}\text{ M}$

Question

Options

Solution

More Ionic Equilibrium Questions