Avogadro
The History of Avogadro’s Law
Avogadro’s Law was proposed in 1811 by the Italian scientist Amedeo Avogadro. According to his hypothesis:
Three years later, Ampère published a paper with similar ideas, replacing the term “molecule” with “particle.” In 1826, Dumas determined atomic weights from the densities of gases, further supporting the validity of Avogadro’s Law. However, Avogadro’s hypothesis was largely ignored by contemporary chemists for almost fifty years.
What is Avogadro’s Number?
Avogadro’s number represents the number of atoms, molecules, or ions in one mole of a substance:
This number is a fundamental constant in chemical calculations and holds significant importance in the field of chemistry.
Avogadro’s Law
According to Avogadro’s Law, different gases at the same temperature and pressure contain an equal number of molecules in equal volumes.
This law states that the volume (V) of a gas is directly proportional to the number of moles (n):
V ∝ n
If a gas is measured under two different conditions at constant temperature and pressure, the relationship between the initial and final states of the gas can be expressed as follows:
Where:
- V₁ and V₂: Volume of the gas
- n₁ and n₂: Number of moles of the gas