If 6.5g of zinc react with 5.0g of HCl , according to the following reaction

Question

Zn + 2HCl _ ZnCl2 + H2
a. Wich substance is the limiting reactant?
b. How many grams of the reactant remains unreacted?
c. How many grams of hydrogen would be produced?

Answer 1

6.5g = 0.1 mole Zn
5.0g = 0.14 mole HCl
(a) so, since 0.1 mole Zn reacts with 0.2 mole HCl, the HCl is the limiting reactant here.
Now you can answer the rest ...