You are given the reaction: NaOH + HCl -> NaCl + H2O
For number one, the reaction is the neutralization of a strong acid and a strong base to yield a salt and water. The strong acid is the HCl and the strong base is NaOH. The salt is NaCl.
For number two, the equation is balanced. Na in the reactant side has one atom and also in the product side. O has only one atom in the product and in the reactant. There are 2H’s in the reactant and in the product side (present in H2O, the 2 in H stands for 2 atoms of H). One atom of Cl is present in the reactant and product side.
For number three, the reactants are NaOH-sodium hydroxide and HCl-hydrogen chloride(hydrochloric acid). The products are NaCl-sodium chloride and H2O-water.