How many molecules are there in 1 miligram Au?

30.11 * 10¹⁷ atoms

Explanation:

Given dа ta:

Mass of Au = 1 mg (0.001 g)

Number of molecules / atom = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms, ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 * 10²³ is called Avogadro number.

For example,

Number of moles of Au = mass / molar mass

Number of moles of Au = 0.001 g / 197 g/mol

Number of moles of Au = 5 * 10⁻⁶ mol

Number of atoms:

one mole = 6.022 * 10²³ atoms

5 * 10⁻⁶ mol * 6.022 * 10²³ atoms / 1mol

30.11 * 10¹⁷ atoms