Amixture consists of ag pb and fe metals. which of these metals will react with zncl2

Non of these elements in the mixture will react with Zinc chloride (ZnCl2).
 This is because; silver, lead and iron are below zinc in the reactivity series and therefore, non of these metals can displace Zinc from is salt (zinc chloride).
Metals higher in the reactivity series have the ability to displace less reactive metals from their salts. 

The molar mass of a substance is defined as the mass of 1 mol of that substance, expressed in grams per mole, and is equal to the mass of 6.022 × 10 23 atoms, molecules, or formula units of that substance.