Name ______________________ What’s Cookin

Bonus #4 10/24/05 Due 10/31/05 at start of class

1. Draw the Lewis symbols for the following elements:

a. Hydrogen b. Boron c. Carbon d. Selenium

e. H⁺ f. Oxide g. N h. F

2. Indicate the polarity of the bonds between the bolded atoms:

a) F---CH₃ b) H₃C----CH₃

c) H-----NH₂ d) HO----H

3. Draw the Lewis structure and state the total number of valence electrons, the shape (geometry) of the central atom(s) and if the molecule is polar or not for the molecules below.

a) PH₃ b) CH₃Cl c) CH₃CN

d) HOF e) CO₂ f) NH₃ g) NH₄⁺

4. Compounds like potassium carbonate contain both covalent and ionic bonds, explain.

5. Draw clearly the Lewis structures for the C₂Cl₂H₂ molecule. There are 3 structures that must be drawn and all contain a carbon-carbon double bond. Note if any of these molecule are polar or not.

6. Consider the FeCl₃Br₃ molecule, with Fe as the central atom and the six halides bound to the metal center. The iron is in an octahedral environment, how many possible isomers are there? Draw them below.

7. Consider carbonate ion, CO₃^2- as shown below. How many resonance forms are there? Draw them showing all lone pairs of electrons. Then draw carbonic acid.

8. Show the hydrogen bonding between water and ethanol.

9. Show the hydrogen bonding between ammonia & water and ammonium with water.

10. Are intermolecular forces more significant in the gas phase or the liquid phase. Explain!