B. Balancing chemical equations Directions: Balance the following chemical equations.

1. CaCO3 (s) → CaO(s) + CO2
2. CO(g) + O2(g) → CO2 (g)
3. C6H6 (l) + O2 (g) → CO2 (g) + H2O(l)
4. Mg(s) + AlCl2 (aq) → Al (s) + MgCl2(aq) ​