Question

which has more number of atoms? 100g of N2 or 100g of NH3

Answer 1

must be NH3 because it is a compound

Answer 2

Answer: 100 g of NH3

Explanation:

According to Avogadro's law , 1 mole of every substance contains Avogadro's number $6.023\times 10^{23}}$ of particles.

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of $N_2$ = 28 g/mol

Molar mass of $NH_3$ = 17 g/mol

${\text {moles of}N_2}=\frac{100g}{28g/mol}=3.6moles$

${\text {moles of}NH_3}=\frac{100g}{17g/mol}=5.9moles$

1 mole of  $N_2$ contains =$6.023\times 10^{23}\times 2=12.04\times 10^{23}atoms$

Thus 3.6 moles of $N_2$ contains =$\frac{12.04\times 10^{23}}{1}\times 3.6=43.34\times 10^{23}atoms$

1 mole of  $NH_3$ contains =$6.023\times 10^{23}\times 4=24.09\times 10^{23}atoms$

Thus 5.9 moles of $NH_3$ contains =$\frac{24.09\times 10^{23}}{1}\times 5.9=142.13\times 10^{23}atoms$