The reaction pathway involves the following steps:

Cl2 (chlorine gas) reacts with H2 (hydrogen gas) to form HCl (hydrogen chloride gas):
Cl2 + H2 -> 2HCl

HCl (hydrogen chloride gas) then reacts with NaOH (sodium hydroxide) to form NaCl (sodium chloride) and water (H2O):
HCl + NaOH -> NaCl + H2O

Finally, AgNO3 (silver nitrate) reacts with NaCl (sodium chloride) to form AgCl (silver chloride) and NaNO3 (sodium nitrate):
AgNO3 + NaCl -> AgCl + NaNO3

Therefore, the overall reaction pathway is:
Cl2 + H2 -> 2HCl + NaOH -> NaCl + H2O + AgNO3 -> AgCl + NaNO3