Place the coefficients in the redox reaction using the electronic balance method: a) NO + O2

Place the coefficients in the redox reaction using the electronic balance method: a) NO + O2 = NO2; b) Cl2 + H2O = HClO + HCl; c) KClO3 + S = KCl + SO2; d) CrO3 + H2S + H2SO4 = Cr2 (SO4) 3 + S + H2O

a) 2NO + O2 = 2NO2
N (+2) + 2e -> N (+4) – oxidizing agent | 2
O2 (0) – 4e -> 2O (-2) – reducing agent | one
b) Cl2 + H2O = HClO + HCl
Cl2 (0) – 2e -> 2Cl (+1) – reducing agent | one
Cl2 (0) + 2e -> 2Cl (-1) – oxidizing agent | one
No odds needed.
c) 2KClO3 + 3S = 2KCl + 3SO2
Cl (+5) + 6e -> Cl (-1) – oxidizing agent | 2
S (0) – 4e -> S (+4) – reducing agent | 3
d) 2CrO3 + 3H2S + 3H2SO4 = Cr2 (SO4) 3 + 3S + 6H2O
Cr (+6) + 3e -> Cr (+3) – oxidizing agent | 2
S (-2) – 2e -> S (0) – reducing agent | 3