Argon Protons Neutrons Electrons (And How to Find them?)

Argon has 18 protons, 22 neutrons and 18 electrons.

But how will you find the number of protons, neutrons and electrons in Argon (Ar)?

Well, it is very easy to find the protons, neutrons and electrons of argon atom.

Here I have given a very simple method for finding the protons, neutrons and electrons of argon atom.

Let’s dive right into it!

Finding the Protons, Neutrons and Electrons in Argon

How to find protons?

• The number of protons can be found by knowing the atomic number of that atom. ^[1]

How to find neutrons?

• The number of neutrons can be found by subtracting the atomic number from its atomic mass.

How to find electrons?

• For a neutral atom, the number of electrons can be found by knowing the atomic number of that atom.

Let’s calculate the number of protons, neutrons and electrons in argon.

If you don’t want to read, then you can also watch this video.

#1 Number of Protons in Argon

If you have a periodic table with you, then most of the answers are in front of you.

You can see the elements, their atomic number and their atomic mass from the periodic table.

Now here our element is Argon (Ar).

So from the above periodic table, you can see that the atomic number of argon is 18.

As the atomic number of argon is 18, it has a total of 18 protons in its nucleus.

Thus, the number of protons in Argon is 18.

#2 Number of Neutrons in Argon

In order to find the number of neutrons of an argon atom, you should know its atomic mass first.

The number of neutrons in argon can be obtained by subtracting the atomic number from its atomic mass.

The atomic mass of argon is 39.95 u (which you can round it to 40). ^[2]

So from this atomic mass (i.e 40), you have to subtract its atomic number (i.e 18).

So you will get 40 – 18 = 22.

Thus, the number of neutrons in Argon is 22.

#3 Number of Electrons in Argon

For a neutral atom, the number of electrons and the number of protons are the same.

Here, the argon atom is a neutral atom.

So the number of electrons in argon is equal to its number of protons (which is also equal to its atomic number).

In the beginning, we have found that the number of protons in argon is 18.

Thus, the number of electrons in Argon is 18.

Summary

Number of Protons in Argon

• The number of protons can be found by knowing the atomic number of that atom.
• Number of Protons in Argon = Atomic number of Argon = 18

Number of Neutrons in Argon

• The number of neutrons can be found by subtracting the atomic number from its atomic mass.
• Number of Neutrons in Argon = Atomic mass of Argon – Atomic number of Argon = 40 – 18 = 22

Number of Electrons in Argon

• For a neutral atom, the number of electrons can be found by knowing the atomic number of that atom.
• Number of Electrons in Argon = Atomic number of Argon = 18

I hope you have understood the simple method for finding the protons, neutrons and electrons of argon atom.

Check out related topics for more practice;
Germanium protons neutrons electrons
Arsenic protons neutrons electrons
Selenium protons neutrons electrons
Bromine protons neutrons electrons
Krypton protons neutrons electrons