When burning 5 g of coal, 5.6 g of carbon dioxide were released. Calculate the mass fraction of carbon in coal.

The coal combustion reaction is described by the following chemical reaction equation:

C + O2 = CO2;

One mole of coal produces one mole of carbon dioxide.

Let’s determine the amount of carbon dioxide.

M CO2 = 12 + 16 x 2 = 44 grams / mol;

N CO2 = 5.6 / 44 = 0.1273 mol;

Find the mass of 0.1273 mol of carbon.

M C = 12 grams / mol;

m C = 12 x 0.1273 = 1.5276 grams;

Let’s calculate the mass fraction of carbon in coal.

K C = 1.5276 / 5 = 0.30552 = 30.552%