Test Review Chapter 7
(Chemical Bonding)
The first page of the test will be matching. Any or all definitions given in the
notes or book are fair game.
Any of the questions or type of problems from the home work or book are also
fair game for the test.
For sure you should be able to :
1. Combine ions to form compounds and name them.
[see W.S. 7-1; 7-2]
2. Be able to write empirical formulas from molecular formulas.
[see W.S. 7-4]
3. Calculate G.M.W. and Formula weight.
[see W.S. 7-1; 7-2]
4. Calculate percent composition.
[see W.S. 7-2]
5. Find the number of moles of a compound or element when given the number
of grams. [see W.S. 7-6]
#grams
# moles = ---------G.M.W.
6. Find the mass of a compound in grams when given the number of moles.
[see W.S. 7-6]
# grams = # moles x G.M.W.
7. Calculate the empirical formula of a compound when given the percent
compositions. [see W.S. 7-6 and in book]
8. Work sheet 7-6 has all of the types of problems which will be on the test. As
well as an essay question.
7. Be able to answer any questions from the rest of this review.
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Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
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1. How many atoms of fluorine are present in a molecule of carbon tetrafluoride, CF4?
a. 1
c. 4
b. 2
d. 5
2. Changing a subscript in a correctly written chemical formula
a. changes the number of moles represented by the formula.
b. changes the charges on the other ions in the compound.
c. changes the formula so that it no longer represents that compound.
d. has no effect on the formula.
3. The formula for carbon dioxide, CO2, can represent
a. one molecule of carbon dioxide.
c. one molar mass of carbon dioxide.
b. 1 mol of carbon dioxide molecules.
d. all of the above.
4. What is the formula for zinc fluoride?
a. ZnF
c. Zn2F
b. ZnF2
d. Zn2F3
5. What is the formula for the compound formed by calcium ions and chloride ions?
a. CaCl
c. CaCl3
b. Ca2Cl
d. CaCl2
6. Name the compound Zn3(PO4)2.
a. zinc potassium oxide
c. zinc phosphate
b. trizinc polyoxide
d. zinc phosphite
7. Name the compound Hg2(NO3)2.
a. mercury(II) nitrate
c. mercury(I) nitrate
b. dimercury dinitrate
d. mercuric nitrate
8. What is the metallic ion in copper(II) chloride?
a. Co2+
c. Cu2+
b. Cl2–
d. Cl–
9. Name the compound CF4.
a. calcium fluoride
c. carbon tetrafluoride
b. carbon fluoride
d. monocarbon quadrafluoride
10. Name the compound N2O4.
a. sodium tetroxide
c. nitrous oxide
b. dinitrogen tetroxide
d. binitrogen oxide
11. Name the compound N2O5.
a. dinickel pentoxide
c. neon oxide
b. dinitrogen pentoxide
d. nitric oxide
12. What is the formula for nitrogen monoxide?
a. N2O
c. NO
b. NOO
____ 13. What is the formula for silicon dioxide?
a. SO2
b. SiO2
d. N2O2
c. Si2O
d. S2O
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____ 14. What is the formula for nitrogen trifluoride?
a. NiF3
c. N3F
b. NF3
d. Ni3F
____ 15. What is the formula for diphosphorous pentoxide?
a. P2PeO5
c. P2O4
b. PO5
d. P2O5
____ 16. The oxidation number of fluorine is
a. always 0.
b. –1 in all compounds
c. +1 in all compounds.
d. equal to the positive charge of all the metal ions in a compound.
____ 17. What is the oxidation number of an uncombined element?
a. –1
c. +1
b. 0
d. 8
____ 18. In a compound, the algebraic sum of the oxidation numbers of all atoms equals
a. 0.
c. 8.
b. 1.
d. the charge on the compound.
____ 19. What is the oxidation number of carbon in CI4?
a. –4
c. +4
b. +1
d. +5
____ 20. What is the oxidation number of hydrogen in H2O?
a. 0
c. +2
b. +1
d. +3
____ 21. What is the oxidation number of magnesium in MgO?
a. –1
c. +1
b. 0
d. +2
____ 22. What is the oxidation number of sulfur in H2SO4?
a. –2
c. +4
b. 0
d. +6
____ 23. Name the compound SiO2 using the Stock system.
a. silica
c. silicon dioxide
b. silicon oxide
d. silicon(IV) oxide
____ 24. The molar mass of an element is the mass of one
a. atom of the element.
c. gram of the element.
b. liter of the element.
d. mole of the element.
____ 25. A formula that shows the simplest whole-number ratio of the atoms in a compound is
the
a. molecular formula.
c. structural formula.
b. ideal formula.
d. empirical formula.
____ 26. The empirical formula for a compound shows the symbols of the elements with
subscripts indicating the
a. actual numbers of atoms in a molecule.
b. number of moles of the compound in 100 g.
c. smallest whole-number ratio of the atoms.
d. atomic masses of each element.
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____ 27. What is the empirical formula for a compound that is 43.6% phosphorus and 56.4%
oxygen?
a. P3O7
c. P2O3
b. PO3
d. P2O5
____ 28. What is the empirical formula for a compound that is 53.3% O and 46.7% Si?
a. SiO
c. Si2O
b. SiO2
d. Si2O3
____ 29. A compound contains 259.2 g of F and 40.8 g of C. What is the empirical formula for
this compound?
a. CF4
c. CF
b. C4F
d. CF2
____ 30. A molecular compound has the empirical formula XY3. Which of the following is a
possible molecular formula?
a. X2Y3
c. X2Y5
b. XY4
d. X2Y6
____ 31. The molecular formula for vitamin C is C6H8O6. What is the empirical formula?
a. CHO
c. C3H4O3
b. CH2O
d. C2H4O2
____ 32. Of the following molecular formulas for hydrocarbons, which is an empirical formula?
a. CH4
c. C3H6
b. C2H2
d. C4H10
Short Answer
33. Explain the term empirical formula. What is the empirical formula of strontium bromide,
SrBr2?
Problem
34. The molar mass of aluminum is 26.981 g/mol and the molar mass of fluorine is 19.00
g/mol. Calculate the molar mass of aluminum trifluoride, AlF3.
35. The molar mass of copper is 63.55 g/mol, the molar mass of sulfur is 32.07 g/mol, and
the molar mass of oxygen is 15.999 g/mol. Calculate the molar mass of copper(II)
sulfate, CuSO4.