- X is calcium carbonate (CaCO3)
- Y is slaked lime
- Z is bleaching powder (CaOCl2)
- G is chlorine gas
X is Calcium. When calcium carbonate reacts with HCl, it gives out CO2 gas.
CaCO3 + HCl → CaCl2 + CO2 + H2O
When CO2 is passed into lime water, it turns milky due to the formation of Calcium carbonate.
Hence, solution Y is lime water
When chlorine gas is passed on dry lime water, it gives bleaching powder which is used for disinfecting water.