Avogadro Number Calculator

Avogadro’s number

Definition:
The number of atoms, molecules and ions present in one gram atom, one gram mole of a compound or one gram ion of an ionic species, respectively is called Avogadro’s number.

It is denoted by N_A. Its value is 6.02 × 10²³.

Examples of atoms:

• 1.008 g of hydrogen atom = 1 mole of H = 6.02 × 10²³ atoms of hydrogen
• 23 g of sodium atoms = 1 mole of Na = 6.02 × 10²³ atoms of sodium
• 238 g of uranium atoms = 1 mole of U = 6.02 × 10²³ atoms of uranium

Explanation:

The number of atoms in one mole of element is 6.02 × 10²³. Different elements have different atomic masses. These different masses of different elements are equal to one mole and one mole of any element contains same number of atoms which is equal to Avogadro’s number (6.02 × 10²³).

It is clear from the example that an atom of Na is approximately 23 times heavier than one atom of H. One atom of uranium is approximately 238 times heavier than one atom of hydrogen.

Examples of molecules:

Just like elements, one mole of different compounds have same number of molecules.

• 18 g of water = 1 mole of water = 6.02 × 10²³ molecules of water
• 180 g of glucose = 1 mole of glucose = 6.02 × 10²³ molecules of glucose
• 342 g of sucrose = 1 mole of sucrose = 6.02 × 10²³ molecules of sucrose

Examples of ions:

One mole of different ions has different masses and contains same number of ions.

• 62 g of NO₃^-1 = 1 mole of NO₃^-1 = 6.02 × 10²³ ions of NO₃^-1
• 96 g of SO₄^-2 = 1 mole of SO₄^-2 = 6.02 × 10²³ ions of SO₄^-2

Conclusion:

It can be concluded from the above discussion that:

1. The number of particles, 6.02 × 10²³, is closely related with one mole of the substance.
2. The Avogadro’s number correlates the number and masses of atoms, molecules and ions in elements and compounds.