2KClO3=2KCl+3O2
M 2KClO3=245
M 3O2=96
X=980*96/245
X=384 g 3O2
m O2= 384/6
m=64 g O2
2Mg+O2=2MgO
M 2MgO= 80
M O2=32
a=64*80/32
a=160 g 2MgO
4Na+O2=2Na2O
M 2Na2O=124
M O2=32
b=64*124/32
b=248 g 2Na2O
4Al+3O2=2Al2O3
M 3O2=96
M 2Al2O3=204
c=384*204/96
c=816 g 2Al2O3
2Zn+O2=2ZnO
M 2ZnO=162
M O2=32
d=64*162/32
d=324 g 2ZnO