Skip to main content
Ch.10 - Chemical Bonding I: The Lewis Model
Chapter 10, Problem 35

Write the electron configuration for oxygen. Then write the Lewis symbol for oxygen and show which electrons from the electron configuration are included in the Lewis symbol.

Verified step by step guidance
1
First, determine the electron configuration of oxygen. Oxygen has an atomic number of 8, which means it has 8 electrons. The electron configuration is filled by adding electrons to the lowest energy orbitals first, following the Aufbau principle, Hund's rule, and the Pauli exclusion principle. The configuration starts with the 1s orbital, then the 2s orbital, and finally the 2p orbitals.
Write the electron configuration for oxygen. The first two electrons will fill the 1s orbital, the next two will fill the 2s orbital, and the remaining four electrons will partially fill the 2p orbital. The electron configuration of oxygen is therefore: $1s^2 2s^2 2p^4$.
Next, write the Lewis symbol for oxygen. The Lewis symbol represents the valence electrons (electrons in the outermost shell) as dots around the element's symbol. For oxygen, the valence electrons are those in the 2s and 2p orbitals.
Place the valence electrons around the symbol 'O' for oxygen. According to the Lewis structure rules, distribute the electrons to minimize repulsion. Start by placing one electron on each of the four sides (top, bottom, left, right) before pairing them. This results in two lone pairs and two single electrons, which are represented as dots around the 'O'.
Identify which electrons from the electron configuration are shown in the Lewis symbol. The electrons in the Lewis symbol for oxygen are the six valence electrons from the 2s and 2p orbitals, specifically the $2s^2 2p^4$ electrons.

Verified Solution

Video duration:
1m
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Electron Configuration

Electron configuration describes the distribution of electrons in an atom's orbitals. For oxygen, which has eight electrons, the configuration is 1s² 2s² 2p⁴. This notation indicates that there are two electrons in the first energy level (1s) and six in the second level (2s and 2p combined). Understanding electron configuration is essential for predicting chemical behavior and bonding.
Recommended video:
Guided course
01:33
Electron Configuration Example

Lewis Symbols

Lewis symbols, or Lewis dot structures, represent the valence electrons of an atom as dots around the element's symbol. For oxygen, the Lewis symbol is represented as 'O' with six dots, indicating its six valence electrons. This visual representation helps in understanding how atoms bond and interact with each other in chemical reactions.
Recommended video:
Guided course
00:52
Lewis Dot Symbols

Valence Electrons

Valence electrons are the outermost electrons of an atom and are crucial for chemical bonding. In oxygen, the valence electrons are the six electrons in the second energy level (2s² 2p⁴). These electrons are involved in forming bonds with other atoms, making them key to understanding molecular structure and reactivity.
Recommended video:
Guided course
02:12
Transition Metals Valence Electrons