Question:
Balance the following ionic equations
(i) Cr2O72- + H+ + I-→ Cr3+ + I2 + H2O
(ii) Cr2O2-7 + Fe2+ + H+→ Cr3+ + Fe3+ + H2O
(iii) MnO-4 + SO2-3 + H+→ Mn2+ + SO42- + H2O
(iv) MnO4- + H+ + Br-→ Mn2+ + Br2 + H2O
Solution:
(i) 6I + Cr2O72- + 14H+ → 2Cr3+ + 3I2 + 7H2O
(ii) Cr2O2-7 + 6Fe2+ + 14H+→ 2Cr3+ + 6Fe3+ + 7H2O
(iii) 2MnO-4 + 5SO2-3 + 6H+→ 2Mn2+ + 5SO42- + 3H2O
(iv) 2MnO4- + 16H+ + 10Br-→ 2Mn2+ + 5Br2 + 8H2O