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Free Practice Quiz Question List

1 Atomic Structure and Electron Configurations Online Quiz Questions

Use this free practice quiz with 20 questions to review 1 Atomic Structure and Electron Configurations, test your knowledge, and prepare for your next test or exam.

20 questions
01
True or false
1 point

True or false: An orbital is a fixed path that an electron follows around the nucleus.

  1. A

    True

  2. B

    False

02
Choose one
1 point

How are elements ordered in the periodic table?

  1. A

    Increasing mass number

  2. B

    Increasing atomic number

  3. C

    Increasing number of electron shells

  4. D

    Increasing number of isotopes

03
Written response
1 point

What is the term for an atom that has lost one or more electrons and has a positive charge?

04
Choose one
1 point

An atom has 8 protons and 10 electrons. Which change would make it a different element?

  1. A

    Changing the number of neutrons

  2. B

    Changing the number of electrons

  3. C

    Changing the number of protons

  4. D

    Rearranging the electrons among orbitals

05
Written response
1 point

What is the maximum number of electrons that an f subshell can hold?

06
True or false
1 point

True or false: The decimal atomic mass shown for many elements is a weighted average of the masses of their naturally occurring isotopes.

  1. A

    True

  2. B

    False

07
Choose all
1 point

Select all statements that correctly describe the rules used to build ground-state electron configurations.

  1. A

    Electrons generally fill lower-energy orbitals before higher-energy orbitals.

  2. B

    Within a set of equal-energy orbitals, electrons pair up before occupying separate orbitals.

  3. C

    Each orbital holds up to two electrons.

  4. D

    Two electrons in the same orbital have opposite spins.

08
Choose all
1 point

Select all accurate statements about valence-electron counts in main-group elements.

  1. A

    Group 1 elements have one valence electron.

  2. B

    Group 2 elements have two valence electrons.

  3. C

    Groups 13–18 generally have three through eight valence electrons.

  4. D

    Helium has eight valence electrons.

09
Choose one
1 point

Which is the ground-state electron configuration of chromium?

  1. A

    [Ar] 3d⁴ 4s²

  2. B

    [Ar] 3d⁵ 4s¹

  3. C

    [Ar] 3d⁶

  4. D

    [Ar] 3d³ 4s³

10
Open ended
1 point

Give the ground-state electron configuration of oxygen and explain how the Aufbau principle, Hund’s rule, and the Pauli exclusion principle account for the arrangement of its 2p electrons.

11
Choose one
1 point

What does the shorthand electron configuration [Ne] 3s¹ represent for sodium?

  1. A

    It means sodium has the same electron configuration as neon and no additional electrons.

  2. B

    It replaces sodium’s first 10 electrons with neon’s configuration, followed by one electron in 3s.

  3. C

    It represents one electron in 3s and 10 electrons in 3d.

  4. D

    It means sodium has lost one electron from a neon configuration.

12
Written response
1 point

An atom has atomic number 13. How many protons does it contain?

13
True or false
1 point

True or false: Two isotopes of the same element have the same number of protons but different numbers of neutrons.

  1. A

    True

  2. B

    False

14
Choose one
1 point

Which description best explains what an orbital represents in an atom?

  1. A

    A fixed path that an electron follows around the nucleus

  2. B

    A region of space where an electron is likely to be found

  3. C

    The entire nucleus of an atom

  4. D

    A route that an electron follows between energy levels

15
Choose one
1 point

A sodium isotope has mass number 2323 and atomic number 1111. How many neutrons does one atom of this isotope have?

  1. A

    10

  2. B

    11

  3. C

    12

  4. D

    23

16
Written response
1 point

An oxide ion, O2−\mathrm{O}^{2-}, has 8 protons. How many electrons does it have?

17
Choose one
1 point

At ground state, three electrons occupy a set of three equal-energy p orbitals. How are the electrons distributed before any pairing occurs?

  1. A

    All three electrons pair in one orbital.

  2. B

    Two electrons pair in one orbital, while the third orbital is empty.

  3. C

    Each orbital receives one electron before any pairing occurs.

  4. D

    Two orbitals receive one electron each, and the third electron remains outside the subshell.

18
Choose one
1 point

A main-group element is in group 16. How many valence electrons does the group-number pattern generally predict?

  1. A

    Four

  2. B

    Six

  3. C

    Eight

  4. D

    Sixteen

19
Fill in the blank
1 point

Neutral iron has the configuration [Ar] 3d6 4s2\mathrm{[Ar]}\,3d^6\,4s^2. When it forms Fe2+\mathrm{Fe^{2+}}, electrons are removed from the subshell first, leaving [Ar] 3d6\mathrm{[Ar]}\,3d^6.

20
Fill in the blank
1 point

The two rows commonly displayed beneath the main periodic table are the and belong to the .