Difference Between Atomic Mass and Atomic Number

Chemistry can sometimes be a little confusing especially when you are studying about elements and atoms and you have terms like atomic mass and atomic number. Often, students tend to mix up these terms and while they sound similar they think they can use them interchangeably. However, that is a wrong practice and it could result in negative marking. In essence, it is important to learn the concepts in a right manner and know the difference between the terms. As such here, we will be learning about the difference between atomic mass and atomic number.

Atomic mass and atomic number may have similarities, but they are used to reveal different characteristics of elements. As per the definitions that have been provided, atomic mass which is also called atomic weight is the measured average mass of an atom of an element. Whereas, atomic number is nothing but the total number of neutrons and protons in the nucleus of an atom.

Difference Between Atomic Mass and Atomic Number

Atomic mass and atomic number of elements are said to closely related because whenever the atomic number is high, the atomic mass is also said to be high. But again that brings us to the question, what is the difference between atomic mass and atomic number? To know the answer, let’s look at some of the key differences below.

Difference Between Atomic Mass and Atomic Number

Atomic Mass

Atomic Number

Atomic mass is associated with the number of neutrons and protons that are present in a particular nucleus of an element.

Atomic number is usually the number of protons present in an element’s nucleus.

It is the average weight of an element.

It is the total number of nucleons in the atom’s nucleus.

Atomic mass is denoted by A

The letter Z is used to represent atomic number.

Atomic mass cannot be be used to define the type of element.

Atomic number mainly helps in the classification and identification of an element.

Atomic mass is also used to classify different isotopes of the same element

Isotopes only share the same atomic number.

Atomic mass is mostly measured using atomic mass unit (amu).

Atomic number is just a digit that is used to place elements in a periodic table.

These are some of the differences between atomic mass and atomic number. To know more about atoms, atomic structure and other chemistry topics you can keep visiting BYJU’s or download our app for interesting content and learning experience.

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