Understanding the Relationship

* Avogadro's Number: One mole of any substance contains 6.022 x 10²³ particles (atoms, molecules, etc.). This is known as Avogadro's number.

Calculations

1. Set up a conversion factor:

(1 mole Fe / 6.022 x 10²³ atoms Fe)

2. Multiply the given number of atoms by the conversion factor:

3.15 x 10²⁴ atoms Fe * (1 mole Fe / 6.022 x 10²³ atoms Fe)

3. Cancel out the units of "atoms Fe" and calculate:

(3.15 x 10²⁴ / 6.022 x 10²³) moles Fe ≈ 5.23 moles Fe

Answer: There are approximately 5.23 moles of iron present in 3.15 x 10²⁴ atoms of iron.