Answer:
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 data:
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.