Zinc chloride can be readily make by reacting solid zinc metal with aqueous hydrochloric acid. The chemical equation is shown below:
Zn + 2HCl --> ZnCl2 + H2
This produces zinc chloride and hydrogen gas. The hydrogen gas bubbles away so zinc chloride will be the only product present. ZnCl2 readily dissolves in water so you will be left with a solution of ZnCl2 in aqueous hydrochloric acid. You can evaporate the water away and the HCl will also go away with it as a gas. This will leave you with solid zinc chloride. If you dry the solid thoroughly, you can measure its mass and then calculate the yield of the reaction based on the amount of zinc metal initially used.