Name _____________________________
Date ________ Pd____
General Chemistry – Unit 6 Review
Chemical Bonding
Types of Chemical Bonds, Role of Energy
1.
Define a chemical bond.
2.
In what terms do we describe the strength of a chemical bond?
3.
Bond breaking always (requires/releases) energy; bond formation always (requires/releases) energy.
4.
The reaction between methane (CH4) and oxygen gas to form carbon dioxide and water is
exothermic. How do you account for this fact in view of your answers to #3?
5.
compounds result when a metallic element reacts with a nonmetal.
6.
A(n)
bond requires the complete transfer of an electron from one atom to another.
7.
Name the type of chemical bonding that exists between the atoms in the hydrogen molecule, H2.
8.
Name the type of chemical bonding that exists between the atoms in the hydrogen fluoride
molecule, HF.
Stable Electron Configurations and Charges on Ions
9.
In virtually every stable compound, each of the atoms has achieved an electron configuration
analogous to that of the
elements.
10. Metals form positive ions by (losing/ gaining) enough electrons to achieve the electron configuration
of the (previous/next) noble gas.
11. Nonmetals form negative ions by (losing/gaining) enough electrons to achieve the electron
configuration of the (previous/next) noble gas.
12. Explain how the atoms in covalent molecules achieve configurations similar to those of the noble
gases. How does this differ from the situation in ionic compounds?
13. Define ionization energy. Define atomic radius. What trends to we see in terms of these two things
based on the results of our graphing activity?
14. On the basis of their electron configurations, predict the formula of the simple binary ionic
compound likely to form when the following pairs of elements react with each other.
a. Ca and O
b. Sr and F
c. Al and S
d. Rb and N
e. Na and Te
Modeling Chemistry
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U6 gen rev 2011
Ionic Bonding and Structures of Ionic Compounds
15. Why is the formula written for an ionic compound such as NaCl the empirical formula, rather than
a molecular formula?
16. Describe, in general terms, the structure of ionic solids such as NaCl.
17. Why are cations always smaller than the atoms from which they are formed?
18. Why are anions always larger than the atoms from which they are formed?
Lewis Structures
19. Why are the valence electrons of an atom the only electrons likely to be involved in bonding to other
atoms?
20. When elements in the second and third periods occur in compounds, what number of electrons in
the valence energy level represents the most stable electron arrangement? Why?
21. Write the Lewis structures. Identify the most stable ion of these elements.
a. N
b. Br
c. Cs
d. Al
e. Ga
f. Xe
22. What is the total number of valence electrons in each of the following molecules?
a. H2S
b. NI3
c. H2SO4
d. H3PO4
Modeling Chemistry
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U6 gen rev 2011
23. Write a Lewis structure for each of the following simple molecules. Show all bonding valence
electron pairs as lines and all nonbonding valence electron pairs as dots. Also write the name of the
compound represented. Are these ionic or molecular compounds?
a. PH3
b. SF2
c. HBr
d. CCl4
24. Write Lewis structures for the following. Write the name of the compound formed. Are these ionic
or molecular compounds?
a. H2S
b. MgO
c. SiH4
d. KCl
25. Explain how atoms in covalent molecules achieve configurations similar to those of the noble gases.
How does this differ from the situation in ionic compounds?
26. Write the formulas for the following compounds and identify them as ionic or molecular:
a. aluminum oxide
_____________________ __________________
b. copper (II) chloride
_____________________ __________________
c. barium nitrate
_____________________ __________________
d. ammonium chloride
_____________________ __________________
e. phosphorus tribromide _____________________ __________________
27. Write the names of the following compounds and identify them as ionic or molecular:
a. Na2SO4
______________________ _______________________
b. CaCl2
______________________ _______________________
c. SiO2
______________________ _______________________
d. FeCl3
______________________ _______________________
e. Mg(OH)2
______________________ _______________________
28. Distinguish between a period and a group or family on the periodic table. How do we use this
information in terms of periodic trends we see?
29. Know where the alkali metals, alkali earth metals, transition metals, inner transition metals,
halogens and noble gases are on the periodic table.
Modeling Chemistry
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U6 gen rev 2011