Explanation:
The reaction is CaCO
3
+2HCl→CaCl
2
+H
2
O+CO
2
.
Thus, 2 moles of HCl reacts with one mole of calcium carbonate to produce one mole each of calcium chloride, water and carbon dioxide respectively.
Hence, 3 moles of HCl will react with excess of calcium carbonate to produce 3×
2
1
=1.5 mol of carbon dioxide
