Question

In the laboratory a chemist is required to prepare a solution of PbCl2 with a concentration of 0.002M, is it possible at 25⁰C? At what temperature will it be possible to prepare this solution?

Answer 1

Answer:

Yes!, it is be possible to prepare the solution of PbCl₂ at 25⁰C

Explanation:

For ionic dissociation of PbCl₂; we have

PbCl₂   ⇄     Pb²⁺(aq)     + 2Cl⁻(aq)

At Temperature (T) = 25⁰C; Solubility product constant $(K_{sp}) = 1.7*10^{-5}$

$K_{sp}= [Pb^{2+}][Cl^-]^2$

$K_{sp}= [x}][2x]^2$

$K_{sp}= 4x^3$

$1.7*10^{-5}=4x^3$

$x^3 =\frac{1.7*10^{-5}}{4}$

$x^3 =4.25*10^{-6}$

$x =\sqrt[3]{4.25*10^{-6}}$

x = 0.016 M

Since equilibrium concentration of PbCl₂ (i.e 0.016 M ) is greater than the given concentration of PbCl₂ (i.e 0.002 M); then it is possible to prepare a solution of PbCl₂ at 25⁰C.