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Answer the following.
Complete and balance the following reactions: (a) (b)
Complete and balance the following reactions:
(a) $\text{K}_2\text{Cr}_2\text{O}_7 + \text{H}_2\text{SO}_4 + \text{H}_2\text{S} \rightarrow \underline{\qquad} + \underline{\qquad} + \underline{\qquad} + \underline{\qquad}$
(b) $\text{KMnO}_4 + \text{H}_2\text{SO}_4 + \text{KI} \rightarrow \underline{\qquad} + \underline{\qquad} + \underline{\qquad} + \underline{\qquad}$
Answer
Answer
AIEquations: $\mathrm{K_{2}Cr_{2}O_{7}} + 4\mathrm{H_{2}SO_{4}} + 3\mathrm{H_{2}S} \longrightarrow \mathrm{K_{2}SO_{4}} + \mathrm{Cr_{2}(SO_{4})_{3}} + 7\mathrm{H_{2}O} + 3\mathrm{S}$ $2\mathrm{KMnO_{4}} + 8\mathrm{H_{2}SO_{4}} + 10\mathrm{KI} \longrightarrow 6\mathrm{K_{2}SO_{4}} + 2\mathrm{MnSO_{4}} + 8\mathrm{H_{2}O} + 5\mathrm{I_{2}}$
(a) $\mathrm{K_2Cr_2O_7 + 4H_2SO_4 + 3H_2S \rightarrow K_2SO_4 + Cr_2(SO_4)_3 + 7H_2O + 3S}$
(b) $\mathrm{2KMnO_4 + 8H_2SO_4 + 10KI \rightarrow 6K_2SO_4 + 2MnSO_4 + 8H_2O + 5I_2}$
From ISC 2026 Improvement Chemistry Paper 1, question 12(i).
Check your working with the Chemical equation balancer: balance any equation, ionic and redox ones too, with the atom count on each side.