Here is an example of how moles can simplify chemical representation and calculation.Įach molecule of water is made up of one oxygen atom and two hydrogen atoms, so one mole of water is composed of a mole of oxygen and two moles of hydrogen. In order to understand how chemicals interact and how molecules within chemical samples interact, Avogadro’s number must be used. It is done so that weight can be compared with the number of atoms within the substance (as defined by the number of moles) since weight is easier to keep track of than the number of atoms in the chemical sample.Ĭalculations involving more than one chemical require the use of Avogadro’s number and moles. By representing 6.02214076 × 10 23 atoms, moles are used in chemical computations. The chemical reactions involve billions of atoms interacting with one another and being rearranged however, it would be impossible to represent the movement of billions of atoms.ĭespite that, scientists still need a unit of measurement that can represent billions of elementary entities. As a result, the number of atoms is 6.02214076 × 10 23, which is called Avogadro’s number.Īvogadro’s number and the mole are important concepts in chemistry. There is the same number of elementary entities within one mole of carbon 12 as there are atoms. Scientists use moles as a way to measure the number of elementary entities found in a sample of chemicals. A mole is a unit of measurement that is used to state the amount of a substance.

In the case of moles, however, this definition doesn’t help much.

The molar mass of a chemical substance is the mass that one mole of that substance possesses, the mass that one mole of a given substance possesses. A molecule of O2 has a mass of 2 × 16 = 32 amu.

Molar mass