Question

A sample of chalk contains clay as impurity. The clay impurity loses 11% of its weight as moisture on prolong heating. 5 g of chalk on heating shows a loss in weight (due to evolution of CO2 and water) by 1.1 g. Calculate % of chalk in the sample.

Answer 1

Hey dear,

● Answer -
Percentage of chalk in sample = 33.33 %

● Solution -
Let, Mass of chalk be x g.
Then, mass of clay = 5-x g

Loss of CO2 from chalk
= M(CO2)/M(CaCO3) × x
= 44 / 100 × x
= 0.44x

Loss of water from clay
= 11/100 × (5-x)
= 0.55-0.11x

Total loss of CO2 & H2O,
1.1 = 0.44x + 0.55-0.11x
0.55 = 0.33x
x = 1.67 g

Mass of chalk in sample is 1.67 g.

Percentage of chalk in sample
= 1.67 / 5 × 100
= 33.33 %

Therefore, % of chalk im sample is 33.33 %.

Thank you...