Avogadro’s Number

Avogadro’s number is a fundamental constant in chemistry and physics that represents the number of particles (atoms, molecules, ions, etc.) in one mole of a substance.

The value of Avogadro’s number is approximately 6.022 x 10²³ particles per mole. This means that if you have one mole of any substance, it will contain exactly 6.022 x 10²³ particles of that substance.

For example, one mole of water (H2O) contains 6.022 x 10²³ water molecules, and one mole of carbon dioxide (CO2) contains 6.022 x 10²³ carbon dioxide molecules.

Avogadro’s number is named after Italian scientist Amedeo Avogadro, who proposed the hypothesis in 1811 that equal volumes of different gases contain the same number of particles, if they are at the same temperature and pressure. This hypothesis was later confirmed by other scientists, and Avogadro’s number became a fundamental constant in chemistry and physics.

Avogadro’s number is important because it allows us to relate the macroscopic properties of a substance (such as its mass or volume) to its microscopic properties (such as the number of particles it contains).