Rules for solving or balancing a chemical equation:-
1. Write an unbalanced equation.
2. Assign oxidation number for each atom.
3. Separate out reactions into two half reactions.
4. Balance all other atoms except H and O in each half reaction.
5. Balance the hydrogen by H+ or OH− .
6. Balance the oxygen atoms by H2O.
7. Make electron gain equivalent to electron loss in the half reactions by multiplying them with respective numbers.
8. Add and simplify the half reactions together.
9. Check for elements and charges are balanced.
The balanced equation for given reaction is:-
2KI+2H2SO4⟶K2SO4+I2+SO2+2H2O