Quantitative Analysis - Carbon & Hydrogen Problem

Description:

Problem

An organic compound contains 79% C and 6.8% hydrogen, the remainder being oxygen.

Calculate the masses of CO₂ and H₂O formed by the complete combustion of 0.20 g of the substance.

Solution

Given, 79% C and 6.8% hydrogen.

Total mass of the organic compound, m = 0.20 g.

We know that, Percentage of carbon (%C) =

12 x m₂ x 100

/

44 x m

Percentage of hydrogen (%H) =

2 x m₁ x 100

/

18 x m

Therefore, mass of CO₂, m₂ =

%C x 44 x m

/

12 x 100

=

79 x 44 x 0.20

/

2 x 100

= 0.579 g

Similarly, mass of H₂O, m₁ =

%H x 18 x m

/

2 x 100

=

6.8 x 18 x 0.20

/

2 x 100

= 0.122 g