2HNO₃ + S = H₂SO₄ + 2NO
S⁰ -6e => S⁺⁶
N⁺⁵ +3e => N⁺²
6 ==> 1
======>6
3 ==> 2
или:
6HNO₃ + S = H₂SO₄ + 6NO₂ + 2H₂O
S⁰ -6e => S⁺⁶
N⁺⁵ + 1e => N⁺⁴
6 ==> 1
======>6
1 ==> 6
4HNO₃ + C = CO₂ + 4NO₂ + 2H₂O
C⁰ -4e => C⁺⁴
N⁺⁵ +1e => N⁺⁴
4==> 1
======>4
1==> 4
10HNO₃ + 3I₂ = 6HIO₃ + 10NO + 2H₂O
I₂° -10e => 2I⁺⁵
N⁺⁵ +3e => N⁺²
10==> 3
=======>30
3==> 10