Practice Problems: Electron Configuration
CHEM 1A
1. Write complete electron configurations for the following atoms:
a) F
b) Al
c) V
d) Cu
e) Kr
2. Write noble gas electron configurations for
3. How many core, outer, and valence electrons
the following atoms:
a) Cd
do each of the following atoms have?
Core Outer Valence
a) H
b) I
b) Si
c) Ba
c) Ti
d) Rn
d) Br
e) U
e) Ag
4. Write orbital notations for the following atoms:
a) O
1s
2s
2p
3s
3p
4s
3d
1s
2s
2p
3s
3p
4s
3d
1s
2s
2p
3s
3p
4s
3d
1s
2s
2p
3s
3p
4s
3d
b) P
c) Cr
d) Co
5. Complete the valence level orbital notation for the following monatomic ions.
a) Fe3+
b) Sn2+
4s
3d
c) Br–
5s
5p
d) Cr3+
4s
4p
4s
3d
6. Which of the ions in Question 5 would be paramagnetic? ___________ diamagnetic? ___________
7. Match the principle or rule to the related statement:
A.
B.
C.
D.
The aufbau principle
Hund’s rule
The Heisenberg uncertainty principle
The Pauli exclusion principle
_____ electrons are described as clouds and
probability
_____ electrons occupy their own orbital
within a sublevel before sharing
_____ electrons occupy the lowest energy
orbital available in the ground state
_____ any unpaired electrons have the same
spin
_____ an orbital can only hold a maximum
of two electrons
8. Arrange the following neutral atoms in order of increasing atomic radii: S, As, Se, Br, Te
9. Which would you expect to be larger, IE2 for potassium or IE3 for scandium?
10. Arrange the following monatomic ions in order of increasing atomic radii: P3–, Cr6+, Ca2+, Cl–, Ti4+