9.
aAl + vH⁺ => cAl³⁺ + dH₂
ult. Al - 3e⁻=> Al³⁺ | *2
ult. 2Al - 6e⁻=> 2Al³⁺
red. 2H⁺ + 2e⁻ => H₂ | *3
red. 6H⁺ + 6e⁻ => 3H₂
2Al + 6H⁺ + 2Al³⁺ + 3H₂
a = 2 ; b = 6 ; c = 2 ; d = 3
Odp: A
10.
uS + wHNO₃ => xSO₂ + yNO₂ + zH₂O
ult. S - 4e⁻ + 2H₂O=> SO₂ + 4H⁺
red. NO₃⁻ + 1e⁻ + 2H⁺ => NO₂ + H₂O | *4
red. 4NO₃⁻ + 4e⁻ + 8H⁺ => 4NO₂ + 4H₂O
S + 4NO₃⁻ + 4H⁺ => SO₂ + 4NO₂ + 2H₂O
S + 4HNO₃ => SO₂ + 4NO₂ + 2H₂O
u = 1 ; w = 4 ; x = 1 ; y = 4 ; z = 2
Odp: D
