0.314 moles
We are given;
We are required to determine the number of moles of CaCl₂
2HCl + Ca(OH)₂→ CaCl₂ + 2H₂O
Moles = Mass ÷ Molar mass
Molar mass = 36.46 g/mol
Moles of HCl = 22.9 g ÷ 36.46 g/mol
= 0.628 moles
From the equation 2 moles of HCl reacts to produce 1 mole of CaCl₂
Thus, moles of CaCl₂ = Moles of HCl × 1/2
= 0.628 moles × 1/2
= 0.314 moles
Thus, the number of moles of CaCl₂ is 0.314 moles