20.0 mL of a 0.125 M solution of potassium iodide is added to 15.0 mL of a 0.235 M solution of lead (II) nitrate. A reaction occurs via the balanced equation below:

Question

2KI(aq)+ Pb(NO3)2(aq) --> 2KNO3(aq) +PBI2(ppt)

How much product can theoretically be produced in the reaction described above?

Answer 1

This is a limiting reagent problem. You know that because amounts for BOTH reactants are given.
Process:
1. mols reactant 1 = ?

2. mols reactant 2 = ?

3. calculate mols product using reactant 1 without regard to reactant 2.

4. Calculate mols product using reactant 2 without regard to reactant 1.

5. It is likely that mols product from steps 3 and 4 will not be the same; the correct answer in limiting reagent problems is ALWAYS the smaller value and the reactant producing that value is the limiting reagent.

6. The grams of the product = theoretical yield = mols (the smaller value) x molar mass.

Here is a step by step example if you need it.
http://www.jiskha.com/science/chemistry/limiting_reagent_problem.html

Answer 2

thank you so much!