Chemical Bonding Questions

1.  Define electronegativity and describe its general pattern on the periodic table. Why do metals generally have lower electronegativity values than do nonmetals?

2.  For covalent, ionic, and metallic bonds describe their properties in terms of relative melting point, electrical conductivity, and how the bond is formed.

3.  Calculate the electronegativity differences between each pair of elements listed. Then indicate whether the bond would mainly be covalent or ionic.

a. H - O b. C - H c. K - F d. O - Cl e. Na - Br f. Ca - O

4.  Describe the following general relationships:

a.  bond strength and size of an atom.

b.  bond strength and number of shared pairs between atoms.

c.  bond strength and electronegativity difference.

5.  Compare and contrast polar covalent and nonpolar covalent chemical bonds.

6.  How are a molecule and a polyatomic ion alike? How are they different?

7.  Hydrogen bonds are important force of attraction between molecules. Playing a vital role in living organisms.

a.  Describe what specific atoms hydrogen bonds occur between.

b.  What role doe hydrogen bonding play in the freezing of water?

c.  What affect does hydrogen bonding have on the boiling point of water?

8.  Draw a diagram showing three ammonia, NH3, molecules next to each other. Make sure the molecules show the basic molecular shape.

a.  Label the ends of each molecule as either partially positive or partially negative.

b.  Put a lower case “b” next to each covalent bond.

c.  Label where each hydrogen bonds occurs.

d.  When ammonia evaporates, which bonds are broken: hydrogen or covalent?

9.  Compare the following properties the two types of intermolecular forces (London-dispersion and dipole-dipole). Do not just say they are different from each other. Be specific.

a.  Relative strength.

b.  Types of molecules the occur between (polar or nonpolar).

10.  Draw the Lewis structures for each of the following compounds. Name the shape of each molecule. Identify each molecule as polar or nonpolar.

a. HCl b. SF2 c. I2

Extra Credit:

a.  For each of the molecules below draw their lewis structure, list their polarity and identify their type of intermolecular forces and hybridization.

i)  PF5 ii) XeCl4 iii) C3H7OH