Quiz Chem II, chapter 11&12

1. Draw an example of an instantaneous dipole, name the kind of intermolecular force associated with this kind of intermolecular force.

2. Draw an example of a permanent dipole. Explain why there is a permanent dipole, use the term electronegativity.

3. Draw how molecules of water align, and clearly mark how this is relative to hydrogen bonding.

4. Calculate how much energy is required to turn 523 grams of water at 100C into steam knowing that it takes 40.7kj/mol.

5. Calculate how many moles were present if 200,000 KJ were required to melt a volume of ice. Knowing that the density of water is 1g/ml figure out approximately how big that ice cube was (use a description like a cup, a watertank, a pool, a pond, a 2 liter bottle, an ocean. Give me a sense you can relate energy to a volume of water that's meaningful to you).

6. What are the ways to speed up how quickly a compound will evaporate?

7. What are the names of phase changes between solids, liquids, and gases (6 total)?

8. Look to page 425 for guidance. Draw the molecule CO2. Why isn't it polar? Draw the molecule NH3. Why is it polar?

9. Copy down the following gas laws: Boyle, gay-Lusac, Charles, Dalton's, Avagadro, combined, Ideal.

10. Heating oil releases approximately -7990kJ/mol of energy when it's burned. It has an average molecular mass of 450g/mol. A chef in a restaurant takes 40L of 25C water and boils away 1/4 of it while making soup.

a. How much energy was required to heat the water to boiling?
b. How much energy was required to boil some of the water?
c. How many moles of heating needed to be burned to make this happen?
d. How many grams of heating oil was required for the soup.

The heat capacity of water is 4.187 kJ/Kg K.

11. A family uses natural gas to heat their home. They burn 200L of natural gas at 1 atm of pressure and 298k. Assuming natural gas releases -895kJ/mol how mnay kJ did they use for heating?