Answer:
The reaction of calcium metal with water to form calcium hydroxide and hydrogen gas can be represented by the following balanced equation:
Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)
In this equation, "Ca" represents calcium metal, "H2O" represents water, "Ca(OH)2" represents calcium hydroxide, and "H2" represents hydrogen gas. The state symbols (s) , (l) and (aq) represent solid, liquid and aqueous state respectively.
This equation represents the transfer of electrons from the calcium metal to the water molecules, resulting in the formation of calcium hydroxide (a base) and hydrogen gas. The equation is balanced, with one calcium atom on the reactant side and one on the product side, and two water molecules on the reactant side and one calcium hydroxide molecule and two hydrogen atoms on the product side.