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What Is A Mol?
Date : 23/10/2023
The mol is a key concept for any level of chemistry, so it is important to understand what it is and what it is used for.
The definition of a mol is "The amount of a substance that has the same weight as 1/12 of a C12 atom"
What this means is if an element has an atomic weight of 20 (for example), 1 mol of the element will weigh 20 grams.
If a molecule of O2 has molecular weight of 32, how much does:
a) 1 mol weigh?
b) 1/2 mol weigh?
c) 2 mol weigh?
A: 32 x 1 = 32g
B: 1/2 x 32 = 16g
C: 2 x 32 = 64g
Now that you understand mols, where are they used?
The first main case is in using the formula Mr (molecular mass) x mol = mass
The second main case is in using the formula concentration = mols/volume
The third main case is in balanced equations, as in the Haber process:
N2 + 3H2 __> 2NH3
This means that for every 1 mol of N2, you need 3 mols of H2. These combine to make 2 mols of NH3
Thank you for reading this article! I hope it helped. Feel free to message me if you have any questions (about this article or any other questions)!
This resource was uploaded by: Akshat
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