Atomic Structure & Electron Configurations

AP Chemistry Unit 1


Unit 1 - Atomic Structure
& Properties




1.1 Moles and Molar Mass
1.2 Mass Spectroscopy of Elements
1.3 Elemental Composition of Pure Substances
1.4 Composition of Mixtures
1.5 Atomic Structure & Electron Configuration
1.6 Photoelectron Spectroscopy
1.7 Periodic Trends
1.8 Valence Electrons & Ionic Compounds
ISPS Chemistry April 2020 page 1 Atomic Structures & Properties

, AP Chemistry Unit 1
1.5 Practice Problems
Consider atoms of the following elements. Assume that the atoms are in the ground state.
1. The atom that contains only one electron in the highest occupied energy sublevel

A S B Ca C O Ga D Sb E Br

2. The atom that contains exactly two unpaired electrons

O
A S B Ca C Ga D Sb E Br

3. Which of the following ground-state electron configurations represents the atom that has
the lowest first-ionization energy?

A 1s22s1 B 1s22s22p2 C 1s22s22p6 O
D 1s22s22p63s1

4. Which of the following is the ground-state electron configurations of the F— ion ?

A 1s22s22p4 B 1s22s22p5 O
C 1s 2s 2p 2 2 6
D 1s22s22p63s23p6

5. Which of the following best represents the ground-state electron configuration for an atom
of selenium?

A 1s22s22p63s23p3 B 1s22s22p63s23p4

O
C 1s 2s 2p 3s 3p 4s 3d 4p
2 2 6 2 6 2 10 4
D 1s22s22p63s23p64s23d104p5


6. How many protons, neutrons, and electrons are in an 56
26
Fe atom?
Protons Neutrons Electrons

O
A 26 30 26

B 26 56 26

C 30 26 30

D 56 26 26

E 56 82 56




ISPS Chemistry April 2020 page 38 Atomic Structures & Properties