Last modified: Sun 01/17/2016 07:00:49 pm
BCE

It is OK to use your textbook, but if you can answers the questions without it that is OK too.

Do not press the RETURN or ENTER key while you are answering these questions. Your browser will interpret either the same as clicking on the Submit key.

Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.


First Name:

Last Name:

School:

1. Write the complete electron configuration for each of the elements below;

a) Na

b) P

c) Cl

2. Effective nuclear charge (Section 8.1 on p. 297 and 298 in your textbook) is defined as the amount of positive charge experienced by an electron in an atom. The effective nuclear charge for any particular electron is determined by subtracting the number of inner core electrons from the total nuclear charge (Z) for the atom. Complete the table below for the elements in Q1. (NOTE an example using carbon (1s2 2s2 2p2) is shown. In the table below a valence electron is defined as an electron in the outer most shell.)

Element

# of protons (Z)

# of electrons in outer most shell (valence electrons)

# of inner core electrons (inner shell(s))

# of electrons between the nucleus and the outer most electrons

Z*eff for a valence e-

C

6

4

2

2

+4

Na

P

Cl

(remember Z*eff is calculated by subtracting the number of inner core electrons from Z, the nuclear charge.)

2. Explain why the Z*eff for the valence electron in sodium is so much smaller compare to the nuclear charge (Z) for sodium.

3. Calculate Z*eff for an electron in the n = 2 shell in sodium.

4. How does the Z*eff for an electron in the n = 2 shell in a sodium atom compare to the Z*eff for a valence electron in a sodium atom?

5. Calculate Z*eff for an electron in the n = 1 shell in sodium.

6. How does the Z*eff for an electron in the n = 1 shell in a sodium atom compare to the Z*eff for a valence electron in a sodium atom?

7. For sodium from which level (the valence level, n = 2 level or the n = 1 level) is the amount of energy to remove an electron the smallest?

Explain.

8. How many electrons does sodium like to lose? (we learned this back in Chapter 2)

9. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

10. If there is one question you would like to have answered in lecture, what would that question be?