Răspuns:
Explicație:
a )M Al2(SO4) 3 =2*27+3*32+ 12*16=54+96+192=342
342g.........54 g Al........96 g S....................192 g O
100g.........x...................y...........................z
x=15,78
y=28 ,07
z= 56,14
b ) CaH2
R m CaH2= ACa: 2AH=40: 2* 1=20: 1
21 g.......20 g......1 g
100 g.......x..........y
x=95,23 y= 4,76
c ) M Mg(NO3)2=24+ 2*14+6*16=24+28+96=148
148g............24g.......28g......96 g
100 x y z
x=16,21 y=18,91 z= 64,86