Question

Consider the following reaction. 2Fe2O3(s)+3C(s)−heat→−4Fe(s)+3CO2(g)

Calculate the number of grams of Fe2O3 needed to react with 12.0 g C.

Answer 1

Molar mass of C = 12.01 g/mol

mass of C = 12 g

mol of C = (mass)/(molar mass)

= 12/12.01

= 0.9992 mol

Balanced chemical equation is:

2Fe2O3(s)+3C(s)−heat→−4Fe(s)+3CO2(g)

According to balanced equation

mol of Fe2O3 needed = (2/3)* moles of C

= (2/3)*0.9992

= 0.6661 mol

Molar mass of Fe2O3,

MM = 2*MM(Fe) + 3*MM(O)

= 2*55.85 + 3*16.0

= 159.7 g/mol

mass of Fe2O3 = number of mol * molar mass

= 0.6661*1.597*10^2

= 1.064*10^2 g

Answer: 106 g