Name: _ _ _ _ _ _ _ _ _ _ _ Class: _ _ _ _ _ _ _ _ _ Date: _ _ __
ID: A
Oxidation Rules and Formulas
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1. The electrons involved in the formation of a chemical bond are called
a. dipoles.
c. Lewis electrons.
b. s electrons.
d. valence electrons.
2. If two covalently bonded atoms are identical, the bond is
a. nonpolar covalent.
c. dipole covalent.
b. polar covalent.
d. coordinate covalent.
3. If the atoms that share electrons have an unequal attraction for the electrons, the bond is called
a. nonpolar.
c. ionic.
b. polar.
d. dipolar.
4. What are shared in a covalent bond?
a. ions
c. electrons
b. Lewis structures
d. dipoles
5. The greater the electronegativity difference between two bonded atoms, the greater the percentage of __ in
the bond.
a. ionic character
c. metallic character
b. covalent character
d. electron sharing
6. A bond that is less than 5% ionic is considered
a. polar covalent.
c. nonpolar covalent.
b. ionic.
d. metallic.
7. The B-F bond in BF3 (electronegativity for B is 2.0; electronegativity for F is 4.0) is
a. polar covalent.
c. nonpolar covalent.
b. ionic.
d. metallic.
8. The percentage ionic character and the type of bond in Br2 (electronegativity for Br is 2.8) is
a. 0%; nonpolar covalent.
c. 0%; pure ionic.
b. 100%; polar covalent.
d. 100%; pure ionic.
9. In a molecule of fluorine, the two shared electrons give each fluorine atom how many electron(s) in the outer
energy level?
a. 1
b. 2
c. 8
d. 32
10. The electron configuration of nitrogen is Is2 2S22p 3. How many more electrons does nitrogen need to satisfy
the octet rule?
a. 1
b. 3
c. 5
d. 8
11. What group of elements satisfies the octet rule without forming compounds?
a. halogen
c. alkali metal
b. noble gas
d. alkaline-earth metal
12. The chemical formula for water, a covalent compound, is H20. This formula is an example of a(n)
a. formula unit.
c. ionic formula.
b. Lewis structure.
d. molecular formula.
13. Compared with nonmetals, the number of valence electrons in metals is generally
a. smaller.
c. about the same.
b. greater.
d. almost triple.
Name: _____________________
ID: A
14. A chemical formula includes the symbols of the elements in the compound and subscripts that indicate
a. atomic mass of each element.
b. number of atoms or ions of each element that are combined in the compound.
c. formula mass.
d. charges on the elements or ions.
15. How many atoms of fluorine are present in a molecule of carbon tetrafluoride, CF4 ?
a. 1
b. 2
c. 4
d. 5
16. The oxidation number of fluorine is
a. always O.
b. -1 in all compounds.
c. +1 in all compounds.
d. equal to the negative charge of all the metal ions in a compound.
17. What is the oxidation number of oxygen in most compounds?
a. -8
b. -2
c. 0
d. +1
18. In a compound, the algebraic sum of the oxidation numbers of all atoms equals
a. O.
c. 8.
b. 1.
d. the charge on the compound.
19. What is the oxidation number of hydrogen in compounds containing metals?
a. -1
c. +1
b. 0
d. the charge on the metal ion
20. How many valence electrons are in an atom of magnesium?
a. 2
b. 3
c. 4
d. 5
21. How does calcium obey the octet rule when reacting to form compounds?
a. It gains electrons.
b. It gives up electrons.
c. It does not change its number of electrons.
d. Calcium does not obey the octet rule.
22. What is the formula of the ion formed when potassium achieves noble-gas electron configuration?
a.
K2+
b.
K+
c.
K 1-
d.
K 2­
23. Which of the following elements does NOT form an ion with a charge of I+?
b. hydrogen
c. potassium
d. sodium
a. fluorine
24. How many electrons does nitrogen gain in order to achieve a noble-gas electron configuration?
a. 1
b. 2
c. 3
d. 4
25. Which of the following occurs in an ionic bond?
a. Oppositely charged ions attract.
b. Two atoms share two electrons.
c. Two atoms share more than two electrons.
d. Like-charged ions attract.
26. An ionic bond is a bond between __
a. a cation and an anion
c. the ions of two different metals
d. the ions of two different nonmetals
b. valence electrons and cations
27. Which of these elements does not exist as a diatomic molecule?
a. Ne
b. F
c. H
d. I
2
Name: ______________________
ID: A
28. Why do atoms share electrons in covalent bonds?
a. to become ions and attract each other
b. to attain a noble-gas electron configuration
c. to become more polar
d. to increase their atomic numbers
29. A bond formed between a silicon atom and an oxygen atom is likely to be __.
a. ionic
c. polar covalent
b. coordinate covalent
d. nonpolar covalent
30. What type of ions have names ending in -ide?
a. only cations
c. only metal ions
d. only gaseous ions
b. only anions
31. When Group 2A elements form ions, they __.
a. lose two protons
c. lose two electrons
b. gain two protons
d. gain two electrons
32. What is the correct name for the N 3- ion?
a. nitrate ion
b. nitrogen ion
c. nitride ion
33. Aluminum is a group 3A metal. Which ion does Al typically form?
a. A1 3 b. A1 3 +
c. A1 5 -
d.
nitrite ion
d.
A1 5 +
34. Which of the following is NOT a cation?
a. iron(III) ion
b. sulfate
c. Ca 2 +
d. mercurous ion
35. In which of the following are the symbol and name for the ion given correctly?
a.
NH4 +: ammonia; H+: hydride
c. OH-: hydroxide; 0 2 -: oxide
b.
C 2 H 3 0 2 -: acetate; C 2 0 4 -
d. P0 3 3-: phosphate; P0 4 3-: phosphite
:
oxalite
36. Which of the following correctly provides the names and formulas of polyatomic ions?
a. carbonate: HC0 3-; bicarbonate: C0 32 ­
b.
nitrite: NO-; nitrate: N0 2 ­
c.
sulfite: S 2 -; sulfate: S03 ­
d.
chromate: Cr0 4 2-; dichromate: Cr 2 0 7 2­
37. Which of the following formulas represents an ionic compound?
a. CS 2
b. BaI2
c. N 2 0 4
38. Which of the following correctly represents an ion pair and the ionic compound the ions form?
a. Ca 2 i", r; CaF 2
b. Na+, Cl-; NaCl 2 c. Ba z+,0 2 -;
d. Pb 4+, 0 2 -;
Ba 2 0 2
Pb 2 0 4
39. Molecular compounds are usually __.
a. composed of two or more transition elements
b. composed of positive and negative ions
c. composed of two or more nonmetallic elements
d. exceptions to the law of definite proportions
40. Which of the following formulas represents a molecular compound?
a. ZnO
b. Xe
c. SOz
3
d.
BeF2