Given the balanced equation:
CaCO3(s) + 2HCl(aq) -->CaCl2(aq) + H2O(l) + CO2(g)
What is the total number of moles of CO2 formed when 20. moles of HCl is completely consumed?
(1) 5.0 mol (3) 20. mol
(2) 10. mol (4) 40. mol
The answer is (2) 10.0 mol. The equation given is balanced. So the ratio of mol number of compound is the ratio of the number before the compound. The HCl and CO2 ratio is 2:1. So the answer is 10.0 mol.