Zinc reacts with hydrochloric acid according to the following equation: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) In a certain experiment, a 3.77 g sample of impure zinc is reacted with excess hydrochloric acid. If 1.09 L of H2 gas is collected at STP, what percentage of the original sample was zinc? Assume that the impurities do not react with HCl.