Calculate the. number of moles of Cu. in 8.0*1021 atoms of Cu

8.0 * 10²¹ atoms contain 1.33 * 10⁻² moles.

Explanation:

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,

18 g of water = 1 mole = 6.022 * 10²³ molecules of water

1.008 g of hydrogen = 1 mole = 6.022 * 10²³ atoms of hydrogen

Given dа ta:

Number of atoms = 8.0 * 10²¹ atoms

Number of moles = ?

Solution:

One mole of Cu = 6.022 * 10²³ atoms

For 8.0 * 10²¹ atoms:

(1 mol / 6.022 * 10²³ atoms) * 8.0 * 10²¹ atoms

1.33 * 10⁻² moles

So, 8.0 * 10²¹ atoms contain 1.33 * 10⁻² moles.