Byjus Logo

What’s the fuss about a Mole?

Team StoryWeavers|October 23, 2020| 1

Welcome back, science enthusiast!

International Mole Day

Today is a special day for all science enthusiasts. It’s International Mole Day. Now, you might probably assume that the day is dedicated to this small, furry, burrowing animal that mostly lives underground.

Baby Mole

Photo Credit : Imgur

However, we are talking about its namesake, the mole that is used in chemistry. What’s that, you ask? Well, a Mole (sometimes, also spelt as mol), in chemistry is of great importance. It is a standard scientific unit that allows us to actually ‘count’ the number of atoms or molecules present in various substances, in a much more convenient way.

You can say that a mole is just a number. Just like,

A dozen = 12

A pair = 2

A mole = 6.02 × 10²³ ( a rather huge number since atoms and molecules are so small!)

So, one mole is the amount of a substance that contains 6.02 × 10²³ atoms or molecules. But why this specific number?

This number is known as the Avogadro constant (NA) and is named after the Italian scientist Amedeo Avogadro.  He was a man of mathematics and physics who gave the hypothesis that equal volumes of different gases contain an equal number of molecules, provided they are at the same temperature and pressure. This molecular theory was later recognised by several scientists as Avogadro’s constant and the number 6.022 x 1023 as Avogadro’s number (NA).

Lorenzo Romano Amedeo Carlo Avogadro, Count of Quaregna and Cerreto was an Italian scientist, who contribution to the molecular theory now known as Avogadro's law.

Lorenzo Romano Amedeo Carlo Avogadro, Count of Quaregna and Cerreto was an Italian scientist, who contribution to the molecular theory now known as Avogadro’s law.

Avogadro’s number

Now that you got the basic understanding of a mole, let’s move on to ‘molar mass’. As you know, a mole of an element is the numeric equivalent of the atomic mass of that element, but in grams. Hence, the molar mass is the atomic mass in grams. In short,

A molar mass is the mass of  6.022 x 1023 of particles. 

For example, if the atomic mass unit (amu) of hydrogen is 1.01 then one mole of hydrogen weighs 1.01 grams.

Similarly,                                                 Carbon (C) =12.01 amu

                                                                          1 mole of C = 12.01 grams

Mole Quiz | Quiz on Avogadro constant

Take a look at some of the interesting Mole Day themes from the past.

Want to learn more about Mole? Dive deep into the topic and learn about Molar mass, Stoichiometry (the field of chemistry that deals with measurements) and much more with this video.

Was this article helpful? Do let us know in the comments below

About the Author

Generic placeholder image
Tanaya Goswami

Books are Tanaya Goswami’s first love and cheesecakes come a close second. Talking about movies, music, calligraphy, politics, and Elon Musk will get you listed under the friends’ section of her diary. Ever since moving on from her job as an English lecturer, she spends her time at BYJU’S crafting stories filled with emotion and sprinkled with sarcasm. Outside of work, she’s either learning something new (French, most recently!) or is curled up with a book and a cup of coffee. She firmly believes that discovering what you don’t know is the key to knowledge and is constantly working towards improving herself. Drop in a line at if you liked her stories, have something nice to say, or if you have compelling ideas to share!

Leave a Comment


Alokendra Mandal

October 25, 2020

Very interesting thing came in our perseverance.


Card image cap