Difference Between Orbit and Orbital

The key difference between orbit and orbital is that orbit is a circular pathway having a fixed path around a central point whereas orbital is an uncertain area around the nucleus of an atom.

Although the terms “orbit” and “orbital” sound similar, these are two different terms. The word orbit is mainly related to planets while the word orbital is related to atoms. Moreover, it is possible to determine the exact movement of an object through an orbit, but the movement of an object through an orbital is uncertain.

CONTENTS

1. Overview and Key Difference
2. What is Orbit 
3. What is Orbital 
4. Side by Side Comparison – Orbit vs Orbital in Tabular Form
5. Summary

What is an Orbit?

An orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star. The term mainly comes under physics, not chemistry. However, let us discuss some details on this topic in order to understand the difference between orbit and orbital.

Usually, an orbit refers to a repeating trajectory. Sometimes, it may refer to non-repeating trajectory as well. An orbit is invisible because it is a pathway, not an object. But, we can determine the dimensions of this pathway by examining the objects that move through this pathway. A force such as gravitational force creates this pathway which pulls the moving object into a curved/ circular motion.

What is an Orbital?

An orbital is a mathematical function that describes the wave-like behavior of either a single electron or a pair of electrons in an atom. Basically, it is the area where we can find the electron at some point at a given moment. However, the movement of an electron does not occur in a fixed pathway. Thus, an orbital is not a fixed circular pathway as an orbit. Moreover, we cannot determine the exact position of the electron or its exact movement. We can only determine the probability of finding the electron around the atomic nucleus. Hence, the orbital is a specific region in the atom.

Furthermore, there is a unique set of values we can use to characterize the atomic orbital in detail. We call them quantum numbers.

1. Energy level of electron (n)
2. Angular momentum number (l)
3. Magnetic quantum number (m)
4. Spin quantum number (s)

We can show an atomic orbital as an electron cloud around the atomic nucleus. Hence, orbital is a specific region in the atom.

What is the Difference Between Orbit and Orbital?

An orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star while an orbital is a mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom. Therefore, the key difference between orbit and orbital is that orbit is a circular pathway having a fixed path around a central point whereas orbital is an uncertain area around the nucleus of an atom.

A significant difference between orbit and orbital is that orbit has a circular shape while orbital has no defined shape. For example, the movement of planets around stars, a satellite around planets, etc. occur through orbits whereas movement of electrons around the atomic nucleus occurs through orbitals.

Below infographic provides more details on the difference between orbit and orbital.

Summary – Orbit vs Orbital

Both orbits and orbitals are invisible because they are not objects but pathways. Though these two terms sound similar, they are very different from each other. The key difference between orbit and orbital is that orbit is a circular pathway having a fixed path around a central point whereas orbital is an uncertain area around the nucleus of an atom.

Reference:

1. “Orbit.” Wikipedia, Wikimedia Foundation, 27 Apr. 2019, Available here.
2. “Atomic Orbital.” Wikipedia, Wikimedia Foundation, 18 Apr. 2019, Available here.

Image Courtesy:

1. “STS-130 Endeavour flyaround 5” By NASA – (Public Domain) via Commons Wikimedia
2. “Atomic-orbital-cloud n4 l3 m0” By Geek3 – Own work; created with hydrogen-cloud in PythonThis PNG graphic was created with Python (CC BY-SA 4.0) via Commons Wikimedia