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Basic Mass and Moles chemistry equations in flame photometry

Basic Mass and Moles chemistry equations in flame photometry

The equation between Mass and Moles is probably one of the most important relationships that chemists use in everyday work.

When using a flame photometer, you’ll eventually reach a stage where you cannot avoid using mathematics.

The unit of Moles was created by early chemists to give a relative weight of an atom in relation to their atomic particle makeup.


What is a Mole in chemistry?

A mole is defined as the base unit of amount of substance in the International System of Units.

This is also known as Avogadro's number, or the Avogadro Constant.

It is defined as exactly 6.02214076×10²³ elementary entities (6.02 × 10 23 per mole), which is 602,000,000,000,000,000,000,000 per mole.

The units may be atoms, molecules, ions, or electrons, depending on the nature of the substance and the character of the reaction (if any).

What is Mass in chemistry?

Mass is fundamentally a measure of the amount of matter contained within an object.

In effect, it is the resistance that a body of matter offers to a change in its position or speed upon the application of a force.

How do you calculate the equation between Mass and Moles?

The equation for this relationship can be given in two different forms:

Mr x Mol = Mass


Ar x Mol = Mass


Ar / Mr = Atomic / Molecular relative atomic mass (usually given in grams per Moles)

Mol = units of Moles

Mass = Units of Mass (Grams)

What this equation does is multiply out the Mole portion of the Molecular or Atomic ratio (g/mol), leaving you with a remaining unit of grams of substance.

Thinking of it in another way, a Mole is a theoretical quantity of atoms or molecules.

A gram, meanwhile, is a commonly measured property that has physical grounding. It is much easier to weigh something than count the number of molecules or atoms in it.

From our knowledge of reactions in chemistry, a mass isn’t the thing that is reacting with one another. It is the actual molecules and atoms hitting each other.

Therefore, this equation is acting almost as a bridge between “theoretical reactions” that we can picture in our head and the masses observed in front of us.

Why do we use Ar and Mr?

The only real reason we use Ar and Mr is that Ar is a given value to a single atom. Meanwhile, Mr is the total combined Ar’s of the molecule.

What this is a value of in actuality is if you were to have a pile which contained 6.02214076×10^23 (Avogadro's Constant) atoms or molecules, it would weigh what is stated as its Ar/Mr.

For example, a mole of Carbon 13 atoms would weigh 13 grams, and so on.

However, we will soon release a specific topic on the Mole itself to give further information on this topic.


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