The solubility curve of a solid X (molecular mass = 160) is as show above. 1,000 cm3 of a saturated solution of X at 80°C is cooled to 40°C . The weight of X crystalized out would be
-
A.
10 g -
B.
12 g -
C.
14 g -
D.
16 g -
E.
18 g
Correct Answer: Option D
Explanation
At 80°C, we have (1000cm^{3} = 0.4mol/cm^{3})
40°C = (0.3mol/cm^{3})
hence, the loss in concentration = (0.1mol/cm^{3})
= (0.1 times 160 = 16g)