0.207 moles of magnesium is present in 1.25 x 10²³ atoms of magnesium.
Avogadro's number tells about the number of entities which will present in 1 mole of any substance and it is related to mole as:
1 mole = 6.023 × 10²³
From the above equation it is clear that in 1 mole of any substance 6.023 × 10²³ number of that atoms will present.
In the question it is given that,
Atoms of magnesium atoms = 1.25 × 10²³
No. of mole of magnesium will be calculated as:
Mole of Mg = 1.25 × 10²³ Mg atoms × (1 mole / 6.023 × 10²³ Mg atoms)
Mole of Mg = 0.207 mole.
Hence, 0.207 moles of magnesium is present.
To know more about Avogadro's number, visit the below link:
https://brainly.com/question/1581342
