1. Find the molar mass of chlorine:
* Chlorine (Cl) has a molar mass of 35.45 g/mol. Since chlorine is a diatomic molecule (Cl₂), its molar mass is 2 * 35.45 g/mol = 70.90 g/mol.
2. Calculate the number of moles:
* Divide the given mass by the molar mass:
* moles of Cl₂ = 35.5 g / 70.90 g/mol = 0.5 mol
3. Use Avogadro's number:
* Avogadro's number states that there are 6.022 x 10²³ particles (atoms, molecules, etc.) in one mole of a substance.
4. Calculate the number of atoms:
* Multiply the number of moles by Avogadro's number:
* atoms of Cl₂ = 0.5 mol * 6.022 x 10²³ atoms/mol = 3.011 x 10²³ atoms
Important Note: Since chlorine exists as diatomic molecules (Cl₂), this calculation gives us the number of Cl₂ molecules. To find the total number of chlorine atoms, we would multiply this result by 2.
Therefore, there are approximately 6.022 x 10²³ chlorine atoms in 35.5 g of chlorine.
