Assuming we are required to identify the type of reaction and balance it;
The reaction is a single displacement reaction.
Zinc metal displaces hydrogen atom from hydrochloric acid to form a salt, zinc chloride and hydrogen gas.
To balance the equation, we put coefficients on the reactants and products for the number of atoms of each element to be equal on both sides of the equation.
In this case, the appropriate coefficients are 1, 2, 1 and 1
