fRT where, f is the degree of freedom. Since, H2 and N2 both are diatomic in nature, so their degree of freedom will be same. Number of moles of H2,n1=‌
m1
mH2
where, m1 is given mass =4g and mH2 is molar mass =2g ⇒‌‌n1=‌
4
2
=‌
2
1
Similarly, number of moles of N2, n2=‌
m2
mN2
where, m2 is given mass =7g and mN2 is molar mass =28g ⇒ n2=‌