Răspuns:
calculam in grame:
MMg=24g/mol
MO2=2×16=32g/mol
MMgO=24+16=40g/mol
2×24g....32g....2×40g
2Mg + O2 → 2MgO
4,8g.......xg.......yg
x=4,8×32/2×24=calculeaza
y=4,8×2×40/2×24=calculeaza
calculam in moli
n=m/M=4,8/24=0,2moli Mg
2moli......1mol.......2moli
2Mg + O2 → 2MgO
0,2moli....zmoli......tmoli
z=0,2×1/2= calculeaza
t=0,2×2/2 = calculeaza
Explicație: