Answer:
5.195 x 10²³ molecules ≅ 5.2 x 10²³ molecules.
Explanation:
- It is known that every 1.0 mole of a molecule contains Avogadro's number of molecules (NA = 6.022 x 10²³).
- We need to calculate the no. of moles in 95.75 g of CaCl₂ using the relation:
n = mass/molar mass = (95.75 g)/(110.98 g/mol) = 0.86 mol.
Using cross multiplication:
1.0 mole of CaCl₂ contains → 6.022 x 10²³ molecules.
0.86 mole of CaCl₂ contains → ??? molecules.
∴ 95.75 g of CaCl₂ (0.86 mole) contain = (0.86 mol)(6.022 x 10²³) = 5.195 x 10²³ molecules ≅ 5.2 x 10²³ molecules.
