The reaction sequence starts with chlorine gas (Cl2) reacting with hydrogen gas (H2) to form hydrogen chloride gas (HCl). Next, hydrogen chloride can be further reacted with copper metal (Cu) to form copper(II) chloride (CuCl2). Copper(II) chloride can then react with zinc metal (Zn) to form zinc chloride (ZnCl2). Finally, silver metal (Ag) can react with chlorine gas to form silver chloride (AgCl).