Final answer:
In the reaction CaCl2 + H2O -> CaO + 2HCl, hydrochloric acid (HCl) is on the product side. Balancing the equation ensures the same number of each type of atom on both sides of the reaction.
Step-by-step explanation:
In the chemical reaction CaCl2 + H2O -> CaO + 2HCl, the acid is on the product side represented as HCl (Hydrochloric acid). When balancing the reaction, we ensure the number of atoms for each element is equal on both sides.
The reaction between calcium carbonate and hydrochloric acid can be shown as:
CaCO3 (s) + 2HCl (aq) -> CaCl2 (aq) + CO2 (g) + H2O(l), where hydrochloric acid reacts with calcium carbonate forming calcium chloride, carbon dioxide, and water as products.
In the balanced reaction between hydrogen and chlorine (H2 + Cl2 -> 2HCl), two molecules of hydrochloric acid are produced, demonstrating the conservation of mass.