How many grams of hydrogen chloride are needed to completely react with 195 grams of zinc?

Question

Zn + 2 HCl —> ZnCl₂ + H₂

Approximately how many grams of hydrogen chloride are needed to completely react with 195 grams of zinc?

Answer 1

Zn + 2HCl ==> ZnCl₂ + H₂ ... balanced equation

moles of Zn present: 195 g Zn x 1 mol Zn / 65.38 g = 2.98 mole Zn

moles HCl needed: 2.98 mol Zn x 2 mol HCl/mol Zn = 5.97 mol HCl

mass HCl needed: 5.97 mol HCl x 36.45 g/mol = 217.6 g = 218 g HCl (3 sig figs)