Molecules Problems and Questions
Covalent Bonding
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Draw electron dot diagrams for the following atoms: Ca, B, C, S, and Br.
Where is a “molecular orbital” located specifically?
What actually causes the attraction between atoms in a covalent bond?
What type of bonding occurs between metals and non-metals?
What type of bonding occurs between non-metal atoms?
Explain how the chemical formula for an ionic compound differs from the molecular formula of a molecular
compound (for example, NaCl vs. C2H4).
7. What name is used for a cluster of atoms bonded together with covalent bonds?
Lewis Diagrams
8. Draw Lewis diagrams for the following diatomic molecules: H2 / O2 / F2 / N2 / HBr.
9. Draw Lewis diagrams for the following molecules: H2S / H2O2 / NH3 / HCN.
10. Draw Lewis diagrams for the following simple organic compounds: CH4 / CF2Cl2 / C2H6 / C2H4 / CO2.
11. Draw Lewis diagrams for the following large organic compounds: CH3OH , / C2H2 / CH2O / CH3CH2OH /
CH3OCH3.
12. Draw “stick diagrams” for the following organic molecules: C3H8 and C8H18.
13. In general, how many covalent bonds are made by the following non-metal atoms: N, I, S, C, H, O, and Cl?
14. What category of elements is involved in covalent bonding?
15. How many electrons are involved in each covalent bond?
16. How many electrons (dots or pairs in bonds) should surround each element in a Lewis diagram (excluding
hydrogen)?
17. How many electrons are involved in a bond with a hydrogen atom?
VSEPR Theory
18. What causes a molecule to take a particular shape?
19. What name is used for a molecule containing just four single bonds?
20. What name is used for a molecule with two single bonds and one double bond?
21. Diatomic molecules always have what shape?
Bond and Molecular Polarity
22. What occurs in a non-polar bond?
23. Which atom attracts the shared pair of electrons in a polar bond?
24. What name is used for a molecule that has a partially-positive side and a partially-negative side?
25. Will a molecule always be polar if the molecule contains polar bonds?
Intermolecular Bonding
26. Explain the difference between a covalent bond and an intermolecular bond.
27. Large molecules tend to be solids. What type of intermolecular bonding is involved?
28. Dipole molecules are virtually never gaseous. Explain.
29. Which type of bonding occurs in molecules with –OH or –NH2 groups?
Molecular Binary Compound Naming Rules
 use prefixes that match the number of atoms in the formula (see yellow sheet)
 end the second name with “-ide”
example: N2O3 is dinitrogen trioxide, P4S10 is tetraphosphorus decasulfide
 never start the first name with “mono-“
example: CCl4 is carbon tetrachloride, not monocarbon tetrachloride
 The o or a at the end of a prefix is often dropped when the word following the prefix begins with another vowel;
however, it is okay to have an a before the i in iodide
examples: monoxide (not monooxide) or tetrarsenide (not tetraarsenide); tetraiodide is okay
30. Name the following molecular compounds using prefixes: N2O4 / P2O5 / Cl2O7 / N2O / PF3 / CF4
/ NO / SO3
31. Write the correct formula for the following molecular compounds: tetraphosphorus trisulfide, phosphorus
trichloride, iodine heptafluoride, chlorine trifluoride , tetraphosphorus decoxide, trisilicon tetranitride,
carbon monoxide, and silicon tetraiodide.
32. What are the “common names” of the following compounds: NH3 and CH3?
33. List the formulas of the seven diatomic elements.
34. Macromolecules (or network solids) are large molecules that form from non-metals that can produce large,
repeating structures. Non-metals that can make four bonds can produce network solids such as diamonds
or quartz crystals. Which non-metals can make macromolecules?
The following PsQs are not required, but similar extra-credit questions/problems will be available on the test.
1. What is a coordinate covalent bond?
2. Draw Lewis structures for the following molecules that contain coordinate covalent bonds: (e/c on test)
carbon monoxide, dinitrogen monoxide, sulfur trioxide, ozone (O3).
3. Polyatomic ions are essentially molecules that have added or lost electrons in order to achieve octets. Draw
Lewis diagrams for the following polyatomic ions (indicate the additional electrons with little x’s instead of dots):
carbonate ion, nitrite ion, hydroxide ion, cyanide ion.
4. The sulfate ion contains two coordinate covalent bonds. Draw a Lewis structure for sulfate ion.