Answer:
1.3×10²³ formula unit
Step-by-step explanation:
Given data:
Mass of CaCl₂ = 23.8 g
Number of formula unit = ?
Solution:
Number of moles = mass/molar mass
Number of moles = 23.8 g/110.98 g/mol
Number of moles = 0.21 mol
1 mole of any substance contain 6.022×10²³ formula unit
0.21 mol × 6.022×10²³ formula unit / 1mol
1.3×10²³ formula unit