20,25g xg yg
4Al + 3O2 = 2Al2O3
4 .27g 3.32g 2.102g
Se calculeaza puritatea aluminiului [100-25=75 ] p=75 la suta
Se aplica formula puritatii
p=mp.100 : mt
mp=p.mt :100
mp=75.27:100=20,25 g Al pur
MAl2O3=2.27 +3.16=102------>1mol=102g
Se calc. xsi y din ec.
x=20,25 .3 .32 :4 27=18 g oxigen
y=20,25 .2 .102 :4.27=38,25 g Al2O3