What is the total number of moles of nacl formed when 2 moles of na2cro4 react completely?

The balanced chemical equation for the above reaction is as follows;

2Na₂CrO₄ + 2HCl - - - > Na₂Cr₂O₇ + 2NaCl + H₂O

stoichiometry of Na₂CrO₄ to NaCl is 2:2

the amount of moles of Na₂CrO₄ reacted is equal to the number of moles of NaCl produced.

We are told that Na₂CrO₄ reacts completely, this means that this is the limiting reactant, amount of product forms depends on amount of limiting reactant present.

When 2 mol of Na₂CrO₄ is used up, according to stoichiometry number of NaCl moles formed are equal to that.

Therefore number of NaCl moles formed - 2 mol

Na2CrO4 react with PbCl2 to form PbcrO4 + 2 NaCl

the total number of moles of nacl when 2 Na2crO4 react completely is calculated by use of reacting ration between Na2CrO4 and NaCl which is 1:2

therefore the moles of Nacl is = 2 x2 = 4 moles