1. Determine the number of ions per formula unit:
* MgCl₂ has one magnesium ion (Mg²⁺) and two chloride ions (Cl⁻).
* That's a total of 3 ions per formula unit.
2. Calculate the number of formula units:
* Use Avogadro's number (6.022 x 10²³ formula units/mole) to convert moles to formula units:
4.0 moles MgCl₂ * (6.022 x 10²³ formula units/mole) = 2.409 x 10²⁴ formula units
3. Calculate the total number of atoms:
* Multiply the number of formula units by the number of ions per formula unit:
2.409 x 10²⁴ formula units * 3 ions/formula unit = 7.227 x 10²⁴ ions
Therefore, there are approximately 7.227 x 10²⁴ atoms in 4.0 moles of MgCl₂.
