a.
%37Cl=450/(450+1350).100%=25%
%35Cl=100-25=75%
NTK trung bình=(37.450+1350.35)/(450+1350)=35,5(đvc)
b.
%Cl(AlCl3)=35,5.3/133,5=79,775%
c.
nCl2=0,224/22,4=0,01mol
n35Cl=0,01.75/100=0,0075mol
Số nguyên tử 35Cl=0,0075.6,02.10^23=4,515.10^21(nguyên tử)