Advanced Chemistry Name __________________________ Hour _______

Advanced Chemistry Approximate Timeline

Students are expected to keep up with class work when absent.

CHAPTER 3 – STOICHIOMETRY

Day Plans for the day Assignment(s) for the day

1

3.2 – Atomic Mass 3.3 – The Mole 3.4 – Molar Mass 3.5 – Percent Composition

Assignment 3.0 Assignment 3.1 Read section(s) 3.6

2

3.6 – Determining the Formula of a Compound o Empirical Formula o Molecular Formula

3

3.6 – Determining the Formula of a Compound o Empirical Formula o Molecular Formula

Assignment 3.2 Read section(s) 3.7 – 3.8

4 3.7 – Chemical Equations 3.8 – Balancing Chemical Equations

Assignment 3.3 Read section(s) 3.9 – 3.10

5 3.9 – Stoichiometry 3.10 – Limiting Reactant

o Percent Yield

Assignment 3.4

6 Work on assignment Assignment 3.5

7 Grade & discuss assignment Review for test

8 Chapter 3 Test Read section(s) 4.2 – 4.3

Advanced Chemistry Name __________________________ Hour _______ Study Guides Chapter 3 Quizzes Advanced Chemistry Quiz 3.3 –3.4 3.3 –The Mole

1. Define the term “mole”. 2. Know the number of atoms in one mole. 3. Know the special name given to the number of atoms in one mole. 4. Perform conversions between atoms, moles, and grams.

3.4 –Molar Mass 5. Define the term “molar mass”. 6. Know how to calculate the molar mass of a compound.

Quiz 3.5 –3.6 3.5 – Percent Composition of Compounds

7. Know how to calculate the percent composition of a compound. 3.6 –Determining the Formula of a Compound

8. Define the term “empirical formula”. 9. Calculate the empirical formula of a compound from experimental data. 10. Define the term “molecular formula”. 11. Calculate the molecular formula of a compound from experimental data.

Quiz 3.7 –3.8 3.7 & 3.8 – Chemical Equations & Balancing Chemical Equations

12. Know where to find the product and reactants in a chemical equation. 13. Give the meaning of the following symbols which are commonly found in chemical

equations. a. (s) b. (l) c. (g) d. (aq)

14. What information is given by the coefficients in a balanced chemical equation? 15. Be able to balance a chemical equation.

Quiz 3.9 –3.10 3.9 & 3.10 – Stoichiometric Calculations & Limiting Reactants

16. Define the following terms. a. limiting reactant b. theoretical yield c. percent yield

17. Perform a limiting reactant calculation 18. Perform a calculation involving percent yield.

Study Guide Chapter 3 Test Advanced Chemistry At the completion of chapter 3 you should… 1. Know the definitions of the following terms.

a. Stoichiometry b. Mole c. Avogadro’s Number d. Molar Mass e. Empirical Formula f. Molecular Formula g. Limiting Reactant h. Theoretical Yield

2. Know how to calculate the average atomic mass of an element. 3. Understand and apply the mole concept. 4. Know how to determine the molar mass of a substance. 5. Know how to calculate the percent composition of a compound. 6. Know how to determine the empirical formula of a compound.

a. Starting with the molecular formula b. Starting with grams of elements c. Starting with percent composition

7. Know how to determine the molecular formula of a compound. a. Starting with the empirical formula b. Starting with grams of elements c. Starting with percent composition

8. Know the parts of a chemical equation 9. Be able to balance chemical equations. 10. Be able to solve stoichiometry problems

a. Simple stoichiometry problems b. Limiting reactant problems c. Percent yield problems

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.0 - Vocabulary Define each of the following terms. 1. Stoichiometry

2. Mole

3. Avogadro’s Number

4. Molar Mass

5. Empirical Formula

6. Molecular Formula

7. Limiting Reactant

8. Theoretical Yield

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.1 – Moles and Molar Mass

Show all work. No work = no credit.

1) Given a 500.0 g sample of pure iron:

A) How many moles of iron are present in the sample?

B) How many atoms of iron are present in the sample?

2) A diamond contains 5.0 x 1021 atoms of carbon.

A) How many moles of carbon are in this diamond?

B) How many grams of carbon are in this diamond?

3) Given 4.24 g of C6H6 .

A) Calculate the number of moles of C6H6 in the sample.

B) Calculate the number of molecules in the sample.

4) Given 0.224 mole of H2O.

A) Calculate the mass of the sample.

B) Calculate the number of molecules in the sample.

5) Given 2.71 x 1022 molecules of CO2.

A) Calculate the moles of CO2 in the sample.

B) Calculate the mass of the sample.

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.2 – Percent Composition, Empirical Formulas, and Molecular

Formulas

Show all work. No work = no credit.

1) Calculate the percent composition by mass of the following compounds that are important starting materials for synthetic polymers: A) C3H4O2 (acrylic acid, from which acrylic plastics are made)

B) C4H6O2 (methyl acrylate, from which Plexiglas is made)

C) C3H3N (acrylonitrile, from which Orlon is made) 2) The most common form of nylon (nylon-6) is 63.68% carbon, 12.38% nitrogen, 9.80%

hydrogen, and 14.14% oxygen. Calculate the empirical formula for nylon-6. 3) A sample of urea contains 1.121 g N, 0.161 g H, 0.480 g C, and 0.640 g O. What is the

empirical formula of urea?

Advanced Chemistry Name __________________________ Hour _______ 4) A compound contains only C, H, and N. Combustion of 35.0 mg of the compound

produces 33.5 mg of CO2 and 41.1 mg of H2O. What is the empirical formula of this compound?

5) Maleic acid is an organic compound 41.39% C, 3.47%H, and the rest oxygen. If 0.129

mol of maleic acid has a mass of 15.0 g, what are the empirical and molecular formulas of maleic acid?

6) Determine the empirical and molecular formulas of a compound that contains 26.7% P, 12.1% N, and 61.2% Cl, and has a molar mass of 580 g/mol.

7) A compound contains only C, H, and N. Combustion of 10.86 mg of the compound

yields 16.01 mg of CO2, and 4.37 mg of H2O. The molar mass of the compound is 178.21 g/mol. What are the empirical and molecular formulas of the compound?

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.3 – Balancing Chemical Equations

1) Balance each of the following equations:

A) _____ KO2 (s) + _____ H2O (l) _____ KOH (aq) + _____ O2 (g) + _____ H2O2 (aq)

B) _____ Fe2O3 (s) + _____ HNO3 (aq) _____ Fe(NO3)3 (aq) + _____ H2O (l)

C) _____ NH3 (g) + _____ O2 (g) _____ NO (g) + _____ H2O (g)

D) _____ PCl5 (l) + _____ H2O (l) _____ H3PO4 (aq) + _____ HCl (g)

E) _____ CaO (s) + _____ C (s) _____ CaC2 (s) + _____ CO2 (g)

F) _____ MoS2 (s) + _____ O2 (g) _____ MoO3 (s) + _____ SO2 (g)

G) _____ FeCO3 (s) + _____ H2CO3 (aq) _____ Fe(HCO3)2 (aq)

H) _____ Cr (s) + _____ S8 (s) _____ Cr2S3 (s)

I) _____ NaHCO3 (s) _____ Na2CO3 (s) + _____ CO2 (g) + _____ H2O (g)

J) _____ KClO3 (s) _____ KCl (s) + _____ O2 (g)

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.4 – Reaction Stoichiometry

Show all work. No work = no credit.

1) Over the years, the thermite reaction has been used for welding railroad rails, in

incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is:

Fe2O3 (s) + 2 Al (s) 2 Fe (l) + Al2O3 (s)

A) What mass of iron (III) oxide must be used to produce 15.0 g of iron?

B) What mass of aluminum must be used to produce 15.0 g of iron?

C) What is the maximum mass of aluminum oxide that could be produced?

2) The reaction between potassium chlorate and red phosphorus takes place when you strike a match on a matchbox. If you were to react 52.9 g of potassium chlorate with excess red phosphorus, what mass of tetraphosphorus decaoxide would be produced? The unbalanced reaction is:

_____ KClO3 (s) + _____ P4 (s) _____ P4O10 (s) + _____ KCl (s)

3) The reusable booster rockets of the U.S. space shuttle employ a mixture of aluminum and

ammonium perchlorate for fuel. A possible equation for this reaction is :

3 Al (s) + 3 NH4ClO4 (s) Al2O3 (s) + AlCl3 (s) 3 NO (g) + 6 H2O (l)

What mass of ammonium perchlorate should be used in the fuel mixture for every kilogram of aluminum?

4) One of relatively few reactions that takes place directly between two solids at room

temperature is between barium hydroxide octahydrate (Ba(OH)2 • 8 H2O) and ammonium thiocyante (NH4SCN). In this equation, the “• 8 H2O” in Ba(OH)2 • 8 H2O indicates that eight water molecules surround one Ba(OH)2 molecule.

____ Ba(OH)2 • 8 H2O (s) + ____ NH4SCN (s) ____ Ba(SCN)2 (s) + ____ H2O (l) + ____ NH3 (g)

What mass of ammonium thiocyanate (NH4SCN) must be used if it is to react completely with

6.5 g of barium hydroxide octahydrate?

Advanced Chemistry Name __________________________ Hour _______ 5) Aspirin (C9H8O4) is synthesized by reacting salicylic acid (C7H6O3) with acetic anhydride

(C4H6O3). The balanced equation is:

C7H6O3 + C4H6O3 C9H8O4 + HC2H3O2

A) What mass of acetic anhydride is needed to completely consume 1.00 x 102 g salicylic acid?

B) What is the maximum mass of aspirin (the theoretical yield) that could be produced in this reaction?

Advanced Chemistry Name __________________________ Hour _______ Assignment 3.5 – Limiting Reactants and Percent Yield

Show all work. No work = no credit.

1) Acylonitrile (C3H3N) is the starting material for many synthetic carpets and fabrics. It is

produced by the following reaction:

2 C3H6 (g) + 2 NH3 (g) + 3 O2 (g) 2 C3H3N + 6 H2O (l)

If 15.0 g C3H6, 10.0 g O2, and 5.00 g NH3 are reacted, what mass of acrylonitrile can be produced, assuming 100% yield?

2) DDT, an insecticide harmful to fish, birds, and humans, is produced by the following reaction:

2 C6H5Cl + C2HOCl3 C14H9Cl5 + H2O

chlorobenzene chloral DDT

In a government lab, 1142 g of chlorobenzene is reacted with 485 g of chloral. A) What mass of DDT is formed?

B) Which reactant is limiting? ______________________

C) Which reactant is in excess? _____________________

D) If the actual yield of DDT is 200.0 g, what is the percent yield?

Advanced Chemistry Name __________________________ Hour _______ 3) Consider the following unbalanced reaction:

____ P4 (s) + ____ F2 (g) ____ PF3 (g)

What mass of F2 is needed to produce 120. g of PF3 if the reaction has a 78.1% yield?