A 0.500-g sample of zinc-copper alloy was treated with dilute hydrochloric acid. The hyd...

A 0.500-g sample of zinc-copper alloy was treated with dilute hydrochloric acid. The hydrogen gas evolved was collected by water displacement at and a total pressure of 755 mm Hg. The volume of the water displaced by the gas is 105.7 mL. What is the percent composition, by mass, of the alloy? (Vapor pressure of H₂O at is 26.74 mm Hg.) Assume only the zinc reacts.