Chemistry Reaction Please Help! Im struggling to understand

Question

Given the reaction Pb(NO3)2(aq)+2NaCl(aq)--->PbCl2(s)+@NaNO3(aq)

If 0.0400 moles of Pb(NO3)2 was allowed to react with 0.0500 moles of NaCl, What is the theoretical yield? The limiting reagent? The theoretical yield (in moles of PbCl2) is?

Answer 1

Set up proportions with the amount of starting materials like this:

 

 1 mol Pb(NO3)2  =  0.04 mol Pb(NO3)2 

 1 mol PbCl2                      x

 

x = 0.04 mol PbCl₂

 

 2 mol NaCl  =  0.05 mol NaCl 
1 mol PbCl2              x

 

x = 0.025 mol PbCl₂

 

So now we see that NaCl is the limiting reagent because with the amount of moles of NaCl that we started with, it gave us the least amount of product. The theoretical yield, then, would be .025 moles of lead (II) chloride.