Solubility Product

Q. Calculate the solubility of $A_2{X}_3$ in pure water, assuming that neither kind of ion reacts with water. The solubility product of $A_2{X}_3,K_{sp}=1.1\times {10}^{-23}.$

1. $2.5\times {10}^{-5}mol{L}^{-1}$
2. $2.0\times {10}^{-5}mol{L}^{-1}$
3. $1.0\times {10}^{-5}mol{L}^{-1}$
4. $1.5\times {10}^{-5}mol{L}^{-1}$

Q. What is the solubility of $Al(OH{)}_3$, $(K_{sp}=1\times {10}^{-33})$ in a buffer solution having pH=4?

1. ${10}^{-6}M$
2. ${10}^{-4}M$
3. ${10}^{-3}M$
4. ${10}^{-10}M$

Q.

The Solubility $s$ of $AgCl\left(s\right)$ in pure water and in $0.1M$ $NaCl$ at ${25}^{\circ }C$ respectively are:

$K_{sp}\left(AgCl\right)$ = $2.8\times {10}^{-10}$

1. $1.673\times {10}^{-5}mol/litre$ in water, $1.4\times {10}^{-9}mol/litre$ in $0.1MNaCl$

2. $2.8\times {10}^{-9}mol/litre$ in water, $1.673\times {10}^{-5}mol/litre$ in $0.1MNaCl$

3. $1.673\times {10}^{-5}mol/litre$ in water, $2.8\times {10}^{-9}mol/litre$ $0.1MNaCl$

4. $1.732\times {10}^{-9}mol/litre$ in water, $2.8\times {10}^{-5}mol/litre$ $0.1MNaCl$

Q. Calculate the quantity of sodium carbonate (anhydrous) required to prepare 250 ml of 0.1 M solution:-

1. 2.65 gm
2. 4.95 gm
   
3. 6.25 gm
   
4. None

Q.

The solubility in water of a sparingly soluble salt $A{B}_2$ is $1.0\times {10}^{-5}mol{l}^{-1}$. Its

solubility product number will be

1. $4\times {10}^{-15}$

2. $4\times {10}^{-10}$

3. $1\times {10}^{-15}$

4. $1\times {10}^{-10}$

Q. What is the solubility of a sparignly soluble salt, $PbS{O}_4$ in 0.01 $M$ $N{a}_{2}S{O}_4$ solution ?
$(K_{sp}$ for $PbS{O}_4=1.6\times {10}^{-8})$

1. $1.6\times {10}^{-6}mol{L}^{-1}$
2. $2.6\times {10}^{-9}mol{L}^{-1}$
3. $3.5\times {10}^{-7}mol{L}^{-1}$
4. $0.4\times {10}^{-9}mol{L}^{-1}$

Q. Calculate pH of saturated solution of $Mg(OH{)}_2,K_{sp}$ for $Mg(OH{)}_2$ is $32.0\times {10}^{-12}$.
$\text{Given :}\log 2=0.3010$

1. $9.4$
2. $10.4$
3. $9.8$
4. $11.2$

Q. The molar solubility of $Cd(OH{)}_2$ is $1.84\times {10}^{-5}M$ in water. The expected solubility of $Cd(OH{)}_2$ in a buffer solution of $pH=12$ is:

1. $1.84\times {10}^{-9}M$
2. $2.49\times {10}^{-}M$
3. $6.23\times {10}^{-11}M$
4. $2.49\times {10}^{-10}M$

Q. What is the minimum concentration of $S{O}_4^{2-}$ required to precipitate $BaS{O}_4$ in a solution contining $1.0\times {10}^{-4}$ mole of $B{a}^{2+}?$ ($K_{sp}$ for $BaS{O}_4=4\times {10}^{-10}$)

1. $4\times {10}^{-10}$ M
2. $2\times {10}^{-7}M$
3. $4\times {10}^{-6}M$
4. $2\times {10}^{-3}M$

Q.

The solubility product of $Mg(OH{)}_2$ at ${25}^{\circ }C$ is $1.4\times {10}^{-11}$. The solubility of $Mg(OH{)}_2$ in gm per litre is:

1. $1.4\times {10}^{-3}$

2. $2.8\times {10}^{-3}$

3. $1.11\times {10}^{-6}$

4. $8.7\times {10}^{-3}$

Q. One litre of saturated solution of $CaC{O}_3$ is evaporated to dryness due to which 7.0 mg of residue is left. The solubility product for $CaC{O}_3$ is:

1. $4.9\times {10}^{-5}$
2. $4.9\times {10}^9$
3. $4.9\times {10}^{-9}$
4. $4.9\times {10}^{-7}$

Q. The $pH$ of a solution obtained by mixing $100mL$ of $0.2M$ $C{H}_{3}COOH$ with $100mL$ of $0.2MNaOH$ will be: ($p{K}_{a}forC{H}_{3}COOH=4.74$)

1. 4.74
2. 9.1
3. 8.87
4. 8.87

Q. $K_{\mathrm{sp}}$ of $M(\mathrm{OH}{)}_x$ is $27\times {10}^{-12}$ and its solubility in water is ${10}^{-3}mol{L}^{-1}$. The value of x is .

1. 2
2. 3
3. 4

Q.

The Copper(I) ion forms a complex ion with $C{N}^{-}$ according to the following equation:
$C{u}^{+}\left(aq\right)+3C{N}^{-}\left(aq\right)\rightleftharpoons \left[Cu\right(CN{)}_3{]}^{2-}\left(aq\right);K=1.0\times {10}^{11}$
The concentration of $C{N}^{-}$ at equilibrium when 1.0 M $NaCN$ (1 L) is added to a sufficient amount of $CuBr\left(s\right)$ was found to be $x\times {10}^{-3}M$. The value of $x$ is

$K_{sp}=1\times {10}^{-5}$

Q. A well is dug in a bed of rock containing fluorspar $\left(Ca{F}_2\right)$. If the well contains $20000\text{L}$ of water, what is the amount of $F^{-}$ in it? $K_{sp}=4\times {10}^{-11}({10}^{1/3}=2.15)$

1. 4.3 mol
2. 6.8 mol
3. 8.6 mol
4. 13.6 mol

Q. Which of the following relation(s) is/are correct regarding precipitation?
Here,
$K_{sp}$ is the solubility product and
$Q_{sp}$ ionic concentration product.

1. When $\frac{K_{sp}}{Q_{sp}}<1$ , precipitation takes place.
2. When $\frac{K_{sp}}{Q_{sp}}<1$ , precipitation does not takes place.
3. When $\frac{K_{sp}}{Q_{sp}}>1$ , precipitation takes place.
4. When $\frac{K_{sp}}{Q_{sp}}>1$ , precipitation does not takes place.

Q. At ${25}^{\circ }\text{C}$, $k_{sp}$ of $AgCN$ is $4\times {10}^{-16}$ while $K_a$ of $HCN$ is $4\times {10}^{-10}$. The value of molar solubility of $AgCN$ in $0.01MHN{O}_3$ is ${10}^{-y}$. The value of $y$ is

Q. If the molar solubility $\left(inmol{L}^{-1}\right)$ of a sparingly soluble salt $A{B}_3$​ is $s$. The corresponding solubility product is $K_{sp}$. The solubility $\left(s\right)$ can be written in terms of $K_{sp}$ by the relation:

1. $s=(128K_{sp}{)}^{\frac{1}{4}}$
2. $s={\left(\frac{K_{sp}}{27}\right)}^{\frac{1}{4}}$
3. $s={\left(\frac{K_{sp}}{256}\right)}^{\frac{1}{5}}$
4. $s={\left(\frac{K_{sp}}{3}\right)}^{\frac{1}{4}}$

Q. A solution contains $\left[I^{-}\right]=\left[B{r}^{-}\right]=\left[C{l}^{-}\right]=0.2M$ each.
Then which of the following statements regarding precipitation of sparingly soluble salts $AgCl$, $AgBr$ and $AgI$ is correct:
Given :
$Salt{K}_{sp}(mol{L}^{-1}{)}^2$
$AgCl1.8\times {10}^{-10}$
$AgBr5\times {10}^{-13}$
$AgI8.3\times {10}^{-17}$

1. For, $\left[A{g}^{+}\right]>4.15\times {10}^{-16}M$, precipitation of $AgI$ occurs.
2. For $\left[A{g}^{+}\right]>2.5\times {10}^{-12}M$, precipitation of $AgBr$ occurs.
3. For $\left[A{g}^{+}\right]>9\times {10}^{-9}M$, precipitation of $AgCl$ occurs.
4. For $\left[A{g}^{+}\right]<4.15\times {10}^{-16}M$, precipitation of $AgI$ occurs.

Q. A vessel of 250 litre was filled with 0.01 mole of $S{b}_2{S}_3$ and 0.01 mole of $H_2$ to attain the equilibrium at ${440}^{\circ }\text{C}$ as given below.
$S{b}_2{S}_3\left(s\right)+3H_2\left(g\right)\rightleftharpoons 2Sb\left(s\right)+3H_{2}S\left(g\right)$.
In a separate experiment, this $H_{2}S$ is sufficient to precipitate 1.19 g $PbS$ from $P{b}^{2+}$ solution. Calculate $K_c$ of the above reaction.

Q. Given the solubility product of $Cr(OH{)}_2$ as $2.0\times {10}^{-16}$ at ${25}^{\circ }C$. Calculate the minimum $pH$ when $C{r}^{2+}$ ions start precipitating in the form of $Cr(OH{)}_2$ from a solution having $2\times {10}^{-4}MC{r}^{2+}$ concentration ?

1. 4
2. 9
3. 8
4. 10

Q. Molarity of pure $D_{2}O$ will be (assume density of $D_{2}O$ is $1gm{L}^{-1}$)

1. $55.56M$
2. $18M$
3. $20M$
4. $50M$

Q.

The $K_{sp}$ of $A{g}_{2}Cr{O}_4,AgCl,AgBr$ and AgI are respectively, $1.1\times {10}^{-12},1.8\times {10}^{-10},5.0\times {10}^{-13},8.3\times {10}^{-17}$. Which one of the following salts will precipitate last if $AgN{O}_3$ solution is added to the solution containing equal moles of NaCl, NaBr, Nal and $N{a}_{2}Cr{O}_4$?

1. $A{g}_{2}Cr{O}_4$

2. AgI

3. AgCl

4. AgBr

Q. Which of the following concentrations of $N{H}_4^{+}$ will be sufficient to prevent the precipitation of $Mg(OH{)}_2$ from a solution which is $0.01{\text{M MgCl}}_2$ and $0.1{\text{M NH}}_3\left(aq\right)$? Given that the $K_{sp}$ of $Mg(OH{)}_2=2.5\times {10}^{-11}$ and $K_b$ for $N{H}_3\left(aq\right)=2\times {10}^{-5}$.

1. 0.01 M
2. 0.02 M
3. 0.03 M
4. 0.04 M

Q. What is the concentration of $A{g}^{+}$ ion in $0.01MAgN{O}_3$ that is also $1.0MN{H}_3$ ?
Will $AgCl$ precipitate from a solution that is $0.01MAgN{O}_3$ , $0.01MNaCl$ and $1MN{H}_3$?
Given : Formation constant, $K_{f}of\left[Ag\right(N{H}_3{)}_2{]}^{+}=1.70\times {10}^{7}and{K}_{sp}AgCl=1.8\times {10}^{-10}$

1. $3.5\times {10}^{-9}M$, precipitate of $AgCl$ forms
2. $6.1\times {10}^{-10}M$, precipitate of $AgCl$ does not form.
3. $5.3\times {10}^{-8}M$, precipitate of $AgCl$ forms
4. $2.1\times {10}^{-4}M$, precipitate of $AgCl$ does not form.

Q. The molar solubility in $\left(mol{L}^{-1}\right)$ of a sparingly soluble salt $M{X}_4$​ is ${}^{\prime }{s}^{\prime }$.The molar solubility product is $K_{sp}$. ${}^{\prime }{s}^{\prime }$ is given in terms of $K_{sp}$ by the relation:

1. $s={\left(\frac{K_{sp}}{128}\right)}^{\frac{1}{4}}$
2. $s={\left(\frac{K_{sp}}{256}\right)}^{\frac{1}{5}}$
3. $s=(256K_{sp}{)}^{\frac{1}{5}}$
4. $s=(128K_{sp}{)}^{\frac{1}{4}}$

Q. The solubility of $AgCl$ in water at $298K$ is $1.06\times {10}^{-5}$ mole per litre. Calculate its solubility product at this temperature.

1. $1.12\times {10}^{10}mo{l}^2{L}^{-2}$
2. $1.12\times {10}^{-10}mo{l}^2{L}^{-2}$
3. $1.12\times {10}^{-10}mo{l}^{-2}{L}^2$
4. $1.12\times {10}^{10}mo{l}^{-2}{L}^2$

Q.

Potassium nitrate is shaken with water truly and the mixture so obtained is allowed to pass through the filter paper cone. Will you get any residue?

Q.

The solubility of a salt of weak acid (AB) at pH 3 is $Y\times {10}^{–3}mol{L}^{–1}$. The value of Y is .
(Given that the value of solubility product of AB $K_{sp}=2\times {10}^{–10}$ and the value of ionization constant of HB $K_a=1\times {10}^{–8}$)

Q. The $pH$ of a solution obtained by mixing $100mL$ of $0.2M$ $C{H}_{3}COOH$ with $100mL$ of $0.2MNaOH$ will be: ($p{K}_{a}forC{H}_{3}COOH=4.74$)

1. 4.74
2. 8.87
3. 9.1
4. 8.87