Câu 9.11 nhé:
Phần 1: ta có nO = (moxit - mKL)/16 = 0,6875
Bảo toàn electron
Mg------->Mg+2 +2e
x...........................2x
Al---------->Al+3+3e
y...........................3y
Zn---------->Zn+2+2e
z............................2z
O + 2e--------->O-2
0.6875...........1,375
=> 2x + 3y + 2z = 1,375
Phần 2: BT electron
Mg------->Mg+2 +2e
x...........................2x
Al---------->Al+3+3e
y...........................3y
Zn---------->Zn+2+2e
z............................2z
N+5 + 1e----------->N+4
a a
Ta có 2x + 3y + 2z = a=> a = 1,375 => V=30,8