Question

Calculate the amount of nitrogen gas required to form 7.4 gram of calcium nitride also find the amount of calcium required for the change

Answer 1

are you from st. Thomas school. what is your name? i am from st. Thomas too. this is question of summer assignment of class 8. isn't it?

Answer 2

Answer: Mass of nitrogen gas needed is 0.8344 g and mass of calcium needed is 3.576 g.

Explanation:

$3Ca(s)+N_2(g)\rightarrow Ca_3N_2(s)$

moles of calcium nitride:$\frac{\text{mass of}Ca_3N_2}{\text{molar mass of}Ca_3N_2}=\frac{7.4 g}{248.25 g/mol}=0.0298 moles$

According to reaction, 1 mole of $Ca_3N_2$ is produced from one mole of $N_2$ gas  then 0.0298 moles of $Ca_3N_2$ is produced from : $\frac{1}{1}\times 0.0298 \text{moles of}N_2$  gas.

Mass of $N_2=\text{moles of}N_2\times \text{molar mass of}N_2=0.0298\times 28g/mol=0.8344 g$

According to reaction ,1 mol of N_2 is reaction with 3 mole of Ca then , 0.0298 moles of $N_2$ will react with:$\frac{3}{1}\times 0.0298$ moles of Ca that is 0.0894 moles.

Mass of $Ca=\text{moles of Ca}\times \text{molar mass of Ca}=0.0894 mole\times 40g/mol=3.576 grams$