Calcium carbide reacts with nitrogen and, forms an important fertilizer, calcium cyanamide. How much calcium Cyanamide is formed when 3.2 g of calcium carbide is completely converted into cyanamide?

Reaction of calcium carbide with nitrogen is given below which shows that one mole of calcium carbide forms one mole of calcium cyanamide. Mass present in one mole of calcium carbide is 64 g and in one mole of calcium cyanamide is 80 g. 

$$\begin{gathered} \underset{64 g}{{\mathrm{CaC}}_2}+{\mathrm{N}}_2\to \underset{80 g}{{\mathrm{CaCN}}_2}+\mathrm{C} \\ 64 \mathrm{g} \mathrm{of} {\mathrm{CaC}}_2 =80 \mathrm{g} \mathrm{of} {\mathrm{CaCN}}_2 \\ 3.2 \mathrm{g} \mathrm{of} {\mathrm{CaC}}_2=\frac{80 \mathrm{g} \mathrm{of} {\mathrm{CaCN}}_2}{64 \mathrm{g} \mathrm{of} {\mathrm{CaC}}_2 }\times 3.2 \mathrm{g} \mathrm{of} {\mathrm{CaC}}_2=4 \mathrm{g} \mathrm{of} {\mathrm{CaCN}}_2 \end{gathered}$$