1. Predict how valence electrons would pair up in the AsO4-3 ion.

2. Predict the bond angles in SbCl3 and BH3.

3. Predict the geometric structure of the carbonate ion. What bond angles would you predict. Why?

4. Predict the less polar bond in the following pair: Br-Cl or Br-I

5. Using electronegativity, predict in the order of decreasing polarity the following bonds: N-P, N-O, N-C, N-S, N-F. why?

6. Write the Lewis structures for the following NI3, and PF3.

7. Predict the Lewis structure(s) for the following: N2O

8. Why is the molecular structure of water nonlinear while that for beryllium fluoride is linear?

9. Predict the bond angle between the chlorine atoms in Cl2O. Why?

10. Predict and explain which atom would have the higher second ionization energy: lithium or beryllium.

11. Using the symbol for the previous noble gas to indicate core electrons, write the electron configuration for Z=107.

12. Based on its position in the periodic table, how many 4d electrons are found in Z=44?

13. For Z=84 which orbital is filled last? Why?

14. Arrange the following in order of decreasing atomic size: At, Ba, Cs, Pb.

15. Why do the metallic elements of a given horizontal row typically have much lower ionization energy than do the nonmetallic elements in the same row?