Question

When 17.4g of MnO2 is treated with excess of H2C2O4 in presence of sulphuric acid, 6.72 litre of CO2 is obtained at STP. What is % purity of MnO2​

Answer 1

Answer:

Here, as per the given equation, 1 mole of Cl

2

is formed from 1 mole of MnO

2

Therefore,

Number of moles of Cl

2

is n=

22.4L

2.24L

=0.1 mol

Therefore, Mass of Cl

2

is given by W=87g/mol×0.1 mol=8.7 g

Impurity in MnO

2

=10g−8.7g=1.3g

Percentage impurity=

10g

1.3g

×100=13%