Cliffs AP Chemistry, 3rd Edition

Samples: Multiple-Choice Questions

Note to the student: The AP chemistry exam does not emphasize complex ions or coordi-

nation compounds. There is nothing on the AP exam that involves the concepts of crystal-

field theory, low versus high spin, valence bond theory, or other related areas. If you

understand the questions presented here, then you are basically “safe” in this area of the

exam. Most high school AP chemistry programs do not focus much on this area of chem-

istry because of time constraints.

1. Which of the following is the electron configuration for Ni2+?

A. 1 s^22 s^22 p^63 s^23 p^64 s^23 d^6

B. 1 s^22 s^22 p^63 s^23 p^64 s^23 d^10

C. 1 s^22 s^22 p^63 s^23 p^63 d^8

D. 1 s^22 s^22 p^63 s^23 p^64 s^23 d^8

E. 1 s^22 s^22 p^63 s^23 p^64 s^23 d^4

Answer: C

In forming ions, the transition metals lose their valence (outermost) shell electrons first, fol-
lowed by their outer delectrons. Note: In order for transition metal ions to be colored, the
d orbitals must be partially filled. In this case, the solution containing the Ni2+ion would be
colored (green).

2. As the atomic number of the elements increases down a column,

A. the atomic radius decreases

B. the atomic mass decreases

C. the elements become less metallic

D. ionization energy decreases

E. the number of electrons in the outermost energy level increases

Answer: D

Because the distance between the electrons and the nucleus is increasing, the electrons are be-
coming further away from the nucleus, making it easier to remove them by overcoming the
electrostatic force attracting them to the nucleus. Also, there are more electrons in the way, in-
creasing interference (the electron shielding effect).

Part II: Specific Topics