This is a series of chemical reactions involving the compound ethyl chloride (C2H5Cl).

C2H5Cl can react with water (H2O) to form ethanol (C2H5OH) and hydrogen chloride (HCl):
C2H5Cl + H2O -> C2H5OH + HCl

Ethanol (C2H5OH) can lose a hydrogen molecule (H2) to form ethylene (C2H4) and water (H2O):
C2H5OH -> C2H4 + H2O

Ethylene (C2H4) can undergo hydrogenation to form ethane (C2H6):
C2H4 + H2 -> C2H6

Therefore, the given series of reactions can be summarized as:
C2H5Cl -> C2H5OH -> C2H4 -> C2H6