In the production of Zinc sulfide, 36.8 g of zinc is made to react with 19.4 g of sulfur. 

Zn + S -> ZnS

a. How many grams of ZnS is produced when zinc is completely used up? answer: 54.57 g Zns

b. Which reactant is the limiting reagent? answer: Zn

c. How many grams of the excess reagent are left? answer: 1.28 g S