a) p=1atm
T=273°K
R=0.082 atm/mol×K
P×V=niuRT
n=m/M
M, H2=1×2=2g/mol
n=3/2=1.5 moli
V=niuRT/P=1.5×0.082×273/1=33.57L
b) 1mol NH3.........6.023×10^23molec NH3
X........................12.046×10^25molec
X=12.046×10^25/6.023×10^23=200 moli NH3
1mol.............22.4l
200moli......y
Y=200×22.4=4480 l