Respuesta :

Answer:

5.57 x 10^24 atoms of Mg

Explanation:

1 mole = 6.023x10^23 items, by definition.  Atoms, in this case.

0.25 moles would be (0.25mole Mg )(6.023x10^23 atoms Mg/mole Mg) = 5.57 x 10^24 atoms of Mg