Name: _______________________________
Date: _______________________________
Empirical and Limiting Reactant Dry Lab
1. Calculate the percent composition of each element in aspirin, C9H8O4
2. The drug, timolol, has a molecular mass of 432 g/mol. An elemental analysis shows that
the drug is composed of 49.4% C, 7.64% H, 17.7% N, 15.2% O, and 10.1% S. What is
the molecular formula for timolol?
3. Given that a compound contains 63.15% ca
on, 31.55% oxygen and 5.3% hydrogen:
What is its empirical formula?
If its molecular weight is approx XXXXXXXXXXg/mol, what is its molecular formula?
4. Given that a compound contains 46.87 % iron, 17.33 % phosphorous and 35.81 %
Oxygen and has a molecular mass of 357 g/mol. Calculate the empirical and molecular
formulas.
5. What is the empirical formula of a compound that is 24.2 % Cu, 27.0 % Cl, and 48.8 %
O?
6. If I have 5.3 mol of N2H4 how many moles of NH3 do I have, given the following
alanced equation?
3N2H4 (l) → 4NH3 (g) + N2 (g)
7. Ammonia reacts with hydrogen chloride to produce ammonium chloride. Calculate the
number of grams of ammonium chloride from a reaction of 3.0 g NH3 and 5.0 g HCl.
___NH3 (g) + ____HCl (g) → NH4Cl (g)
8. A chemist reacts 25.9 g of aqueous nickel (II) chloride with 10.0 g of aqueous sodium
hydroxide to produce a solid in an aqueous solution. The reaction produced 9.5 g of the
solid product. Write the chemical reaction and balance, calculate the theoretical yield,
identify the limiting reactant, identify what type of reaction occu
ed and calculate the
percent yield.
9. A reaction vessel contains 10.0 g of CO and 10.0 g of O2. How many grams of CO2
could be produced?
2CO (g) + O2 (g) → 2 CO2 (g)
10. Baking soda can be made in large quantities by the following reaction. If 10.0 g of
sodium chloride reacts with excess of the other reactants and 4.2 g of baking soda
(NaHCO3), is isolated, what is the percent yield of the reaction?
NaCl (aq) + NH3 (aq) + CO2 (aq) + H2O (l) → NaHCO3 (s) + NH4Cl (aq)
11. If 0.154 g of Cu react with 0.483 g of AgNO3 to produce Ag. The actual amount of Ag
produced was 0.299g. What is the percent yield of Ag according to the following
equation?
Cu (s) + 2AgNO3 (aq) → 2Ag (s) + Cu(NO3)2 (aq)
12. Silver nitrate solution reacts with calcium chloride solution to produce two products.
One product forms a solid at the bottom of the beaker and the other is a solution. If 21.5
g of silver nitrate reacts with 8.40 g of calcium chloride. What is the theoretical yield of
the solid product? Which of the two reactants is the limiting reagent? If the solid
product has a mass of 8.69 g, what is the percent yield of the solid?
13. In a laboratory, a reaction of 0.598 g of lead (II) nitrate with 0.641 g of potassium iodide
esulted in a precipitate. The amount of precipitate produced from the reaction was
0.748g.
a. Complete and balance the chemical reaction.
. What type of reaction is in part (a) (2 answers)
c. Calculate the theoretical yield and identify the limiting reactant?
d. Calculate the percent yield?