EOC REVIEW FOR
ELECTRON CONFIGURATION
ORBITAL NOTATION
1s
2s
2p
3s
3p
1. What element is this?
2. Draw the orbital notation for carbon
3. What block has groups 1 & 2?
4. What block is Sn in?
5. What block is Lanthanium in?
6. What block includes the transition elements?
7. An atom having an electron configuration of 1s 2 2s 2 2p6 3s 2 3p4 would be an atom of?
8. Write the electron configuration of each a. chromium
b. sulfur
c. magnesium
d. sodium
Practice Problems
Determine the noble gas notation of each of the following.
9. Xe
10. Ac
11. Zr
In the following electron configuration, label each number and letter 12. with the correct quantum number representative. 4s2
The statement that no two electrons in the same atom can have the same four quantum numbers is a restatement of
a. Bohr’s law.
b. Hund’s rule.
c. the Aufbau principle.
d. the Pauli exclusion principle.
According to the Aufbau principle, which of the following sublevels is lowest in energy?
a. 3d
b. 4s
c. 4p
d. 5s
In a ground­state hydrogen atom in which orbital is the electron?
a. 1s
b. 2s
c. 2p
d. 3s
How many electrons are present in an atom of calcium that has the electron configuration 1s22s22p63s23p64s2?
a. 6
b. 16
c. 20
d. 36
The ground­state electron configuration of neon is 1s22s22p6 In this arrangement, how many of neon’s p orbitals are completely filled?
a. 1
b. 2
c. 3
d. 6
Oxygen has an electron configuration of 1s22s22p4 In this arrangement, how many inner­shell electrons does oxygen have?
a. 1
b. 2
c. 4
d. 8
The noble­gas notation for the electron configuration of bromine is [Ar] 3d104s24p5. How many unpaired electrons are there in an atom of bromine in the ground state?
a. 0
b. 1
c. 3
d. 5
A ground­state atom of which element has one electron in its fourth and outermost main energy level?
a. K
b. Na
c. B
d. Ga
Separating unpaired electrons into as many orbitals as possible
a. places the electrons farther from the nucleus.
b. results in more valence electrons.
c. minimizes the repulsion between electrons.
d. produces a greater spin quantum number