Chemistry Homework

Question

1.6 mol Zn and 7.6 mol HCl react according to the equation Zn + 2 HCl −→ ZnCl2 + H2 . If the limiting reactant is Zn, calculate the amount of ZnCl2 formed. Answer in units of mol.

Answer 1

Zn + 2 HCl −→ ZnCl2 + H2

1.6 mol Zn (1 mol ZnCl2/1 mol Zn) = 1.6 mol ZnCl2

7.6 mol HCl (1 mol ZnCl2/2 mol HCl)=3.8 mol ZnCl2

Since less ZnCl2 forms from Zn than from HCl, the actual amount of ZnCl2 that forms is 1.6 mol, and Zn is the limiting reactant.