Chemistry - Ionic Equilibrium Question with Solution | TestHub

ChemistryIonic EquilibriumMiscellaneous/MixedEasy2 minPYQ_2020

ChemistryEasynumerical

What is the minimum $pH$ needed to prevent the precipitation of $ZnS$ in a solution i.e. $0 .01 M {ZnCl}_{2}$ and saturated with $0 .1 M H_{2} S$ ?
Given:
$K_{sp}$ of $ZnS = 10^{- 21}$
$Ka$ of $H_{2} S = 10^{- 20}$

Answer:

1.00

Solution:

$K_{s p (Z n S)} = [Z n^{2 +}] [S^{2 -}]$
$[S^{2 -}] = \frac{K_{s p}}{[Z n^{2 +}]} = \frac{1 0^{- 21}}{0.01} = 1 0^{- 19}$
$K_{H_{2} S} = \frac{{[H^{+}]}^{2} [S^{- 2}]}{[H_{2} S]}$
$1 0^{- 20} = \frac{{[H^{+}]}^{2} [1 0^{- 19}]}{0.1}$
$[H^{+}] = 0.1$
$p H = - \log . H^{+}$
$= 1$

Stream:NTA_ABHYASSubject:ChemistryTopic:Ionic EquilibriumSubtopic:Miscellaneous/Mixed

⏱ 2mℹ️ Source: PYQ_2020

Doubts & Discussion

Loading discussions...