1) Aluminum (Al) reacts with oxygen (O2) to yield aluminum oxide. In a reaction, 2.91 g of Al reacted with oxygen to
form 5.50 g aluminum oxide. Calculate the empirical formula of aluminum oxide?
2) What is the minimum amount of LiCl, in grams, necessary to react with 106 g of Pb(C2H3O2)2?
3) In the combustion of octane (C8H18), octane reacts with oxygen. What is the mass of CO2 (in g) that is produced from
the complete combustion of 60.3 g of C8H18?
4) When solutions of silver nitrate and sodium carbonate are mixed, a precipitate is formed.
a) What is the theoretical yield, in grams, of the precipitate that can be made from mixing a solution containing
10.8 g of silver nitrate and another solution containing 4.05 g of sodium carbonate? (8.765 g precipitate)
b) If the reaction yielded only 7.16 g of precipitate, what is the percent yield of the reaction?
5) Piribedil, sold under the brand name Pronoran, is an antiparkinsonian agent medication
a) Elemental analysis of piribedil indicates that it consists of 64.4% C, 6.09% H, 18.8% N, and 10.7% O.
Calculate the empirical formula for piribedil.
The molar mass of piribedil is found by mass spectroscopy to be 298.4 g/mol. Determine the molecular formula
for stavudine.
6) Altretamine, which contains only carbon, hydrogen, and nitrogen, is an antineoplastic chemotherapeutic drug used in
the treatment of ovarian cancer.
a) Combustion analysis of 6.91 g of altretamine produces 13.0 g of CO2 and 5.33 g of H2O. Calculate the empirical
formula for altretamine.
b) The molar mass of altretamine is found by mass spectroscopy to be 210.3 g/mol. Determine the molecular
formula for altretamine.
7) Iron(III) oxide reacts with carbon monoxide according to the following equation:
Fe2O3(g) + 3 CO(g) 2 Fe(s) + 3 CO2(g)
A reaction initially contains 22.55 g Fe2O3 and 14.78 g CO. Once the reaction has occurred, what mass (in g) of the
excess reactant remains?
8) Aspirin can be made in the laboratory by reacting acetic anhydride (C4H6O3) with salicylic acid (C7H6O3) to form aspirin
(C9H8O4) by the reaction shown below C4H6O3(l) + C7H6O3(s) C9H8O4(s) + C2H4O2(l)
In a laboratory synthesis, a student begins with 3.00 mL of acetic anhydride (Density = 1.08 g/mL) and 1.25 g of
salicylic acid. Once the reaction is complete, the student collected 1.22 g aspirin. What is the percent yield of the
reaction?
9) Calculate the mass of KI in grams required to prepare 5.00 ×102 mL of a 2.80 M solution.
