Răspuns:
a) 2Al + 3S => Al2S3
Al2S3 sulfura de aluminiu
b) MAl2S3= 2x27+3×32=15g/mol
150g Al2S3........54gAl.......96gS
100g Al2S3.........x%Al..........y%S
x= 100x54/150=calculează
y=100×96/150=calculează
c)
MS=32g/mol
MAl=27g/mol
2x27g........32g
2Al + 3S => Al2S3
54g..............zg
z=54×32/2×27=32gS