You visited us 3 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Chemistry

Solubility

What is the m...

Question

What is the minimum volume of water required to dissolve 1 g of calcium sulphate at 298 K? (For calcium sulphate, $K_{s p} = 9.1 \times 10^{- 6}$ ).

Open in App

Solution

Let s be the solubility of $C a S O_{4}$ .
$C a S O_{4} ⇌ C a^{2 +} S O_{4}^{2 -}$
$[C a^{2 +}] = [S O_{4}^{2 +}] = s$
$K_{s p} [C a^{2 +}] [S O_{4}^{2 -}] = s \times s = s^{2} = 9.1 \times 10^{- 6}$
$s = 0.003016 M$
The molar mass of $C a S O_{4}$ is $40 + 32 + 64 = 136 g$ .
The solubility in g/L is $0.003017 \times 136 = 0.410 g / L$ .
Hence, 0.41 g dissolves in 1 L.
1 g will dissolve in $\frac{1}{0.41} = 2.43 L$ .

Suggest Corrections

Similar questions

Q. Hard water required for an experiment is not available in a school laboratory. However, the following salts are available in the laboratory. Select the salts which may be dissolved in water to make it hard for the experiment :

(1) calcium sulphate
(2) sodium sulphate
(3) calcium chloride
(4) potassium sulphate
(5) sodium hydrogen carbonate
(6) magnesium chloride

Hard water required for an experiment is not available in a school laboratory. However, following salts are available in the laboratory. Select the salts which may be dissolved in water to make it hard for the experiment

(1) Calcium Sulphate

(2) Sodium Sulphate

(3) Calcium Chloride

(4) Potassium Sulphate

(5) Sodium Hydrogen Carbonate

(6) Magnesium Chloride

Q. A mixture of

100 m m o l

C a (O H)_{2}

and

2 g

of sodium sulphate was dissolved in water and the volume was made up to

100 m L

. The mass of calcium sulphate formed and the concentration of

O H^{-}

in resulting solution, respectively, are:

[Molar mass of

C a (O H)_{2}, N a_{2} S O_{4}

and

C a S O_{4}

are

74, 143

and

136 g m o l^{- 1}

, respectively;

K_{s p}

C a (O H)_{2}

5.5 \times 10^{- 6}]

Q. A sample of hard water contains

0.005 m o l e

of calcium chloride

p e r l i t r e

. What is the minimum concentration of sodium sulphate which must be added for removing the

{C a}^{2 +}

ions from this water sample?

(K_{s p}

C a {S O}_{4} = 2.4 \times 10^{- 5})

Q. A student requires hard water for an experiment in his laboratory which is not available in the neighbouring area. In the laboratory there are some salts, which when dissolved in distilled water can convert it into hard water. Select from the following groups of salts, which when dissolved in distilled water will make it hard.
(a) Sodium chloride, Potassium chloride
(b) Sodium sulphate, Potassium sulphate
(c) Sodium sulphate, Calcium sulphate
(d) Calcium sulphate, Magnesium chloride

Join BYJU'S Learning Program

What is the minimum volume of water required to dissolve 1 g of calcium sulphate at 298 K? (For calcium sulphate, Ksp=9.1×10−6).

Let s be the solubility of CaSO4.CaSO4⇌Ca2+SO2−4[Ca2+]=[SO2+4]=sKsp[Ca2+][SO2−4]=s×s=s2=9.1×10−6s=0.003016MThe molar mass of CaSO4 is 40+32+64=136g.The solubility in g/L is 0.003017×136=0.410g/L.Hence, 0.41 g dissolves in 1 L.1 g will dissolve in 10.41=2.43L.

What is the minimum volume of water required to dissolve 1 g of calcium sulphate at 298 K? (For calcium sulphate, $K_{s p} = 9.1 \times 10^{- 6}$ ).