ch. 9, 10 covalent / metallic bonds & IMF                     70 points                               AP chemistry

Academic Honesty:   The answers on this test are my own and I am using only the allowed set of notes as described in the syllabus.  I have not discussed the test questions with anyone before or during the test nor have I seen the test questions prior to the exam.  If you violate any of the preceding items or do not sign, your semester grade is a F.

                                                                                                Signature:  ___________________

In problems involving any calculation, show your work in an organized manner, include (i) any relevant equation (or formula), (ii) conversion factor(s), (iii) put the proper units in your calculations and answer, and (iv) have the proper number of significant figures in your answer.

1. Using band theory,  [10 points]

a. differentiate between an insulator, conductor, and a semiconductor.  [6 points]

b. rationalize the properties of the mater an insulator, conductor, and a semiconductor.  [4 points]

2.  Describe the two types of alloys; include the relative size of the atoms in the alloy and how is the structure of an alloy similar / different from a metal.  [10 points]

3. Describe the basis of a covalent bond based on electrostatics, i.e. force between charges.  [5 points]

4. Using valence bond theory, describe all bonds in  ___; justify / rationalize your answer.  [15 points]

a. Carbon dioxide

b. Methane

5. sketch / label the vapor pressure versus temperature graph for ethane and propane; clearly label, which curve is for ethane and propane.  Justify / rationalize.  [10 points]

6.  describe the basis of London IMF in a nonpolar compound.  [10 points]

7. Old topics:  [10 points]

a. In regards to mass spectroscopy,  [hint:  it’s your weekly quiz problem]

i. Briefly describe how the mass spectrometer works.  [4 points]

ii. Determine the average atomic mass of zinc based on the below information.  [6 points]