Number of atoms in 558.5 grams Fe ( atomic weight of Fe = 55.85 g / mol) is ?

To find the number of atoms, we use moles and Avogadro’s number.

Step 1: Calculate moles

Moles = mass / molar mass

moles = 558.5 / 55.85 = 10 moles

Step 2: Use Avogadro’s number

1 mole = 6.022 × 10²³ atoms

So,

Number of atoms = 10 × 6.022 × 10²³
= 6.022 × 10²⁴ atoms

Final Answer:

6.022 × 10²⁴ atoms

Key Takeaway:

Convert mass → moles → atoms using Avogadro’s number (6.022 × 10²³).