Answer:
We need 28.5 mL of Calcium solution
Step-by-step explanation:
Step 1: Data given
Density = 1.55 g/mL
Mass of calcium fluoride (CaF2) = 85.8 grams
Molar mass of CaF2 = 78.07 g/mol
Step 2: The balanced equation
Ca + 2HF → CaF2 + H2
Step 3: Calculate moles CaF2
Moles CaF2 = mass CaF2 / molar mass CaF2
Moles CaF2 = 85.8 grams / 78.07 g/mol
Moles = 1.10 moles
Step 4: Calculate moles of Ca
For 1 mol mol CaF2 we need 1 mol Ca^2+
For 1.10 moles CaF2, we need 1.10 moles Ca^2+
Step 5: Calculate mass of Ca^2+
Mass Ca^2+ = moles Ca^2+ / molar mass Ca^2+
Mass Ca^2+ = 1.10 moles * 40.08 g/mol
Mass Ca^2+ = 44.1 grams
Step 6: Calculate volume of Ca^2+
Volume Calcium = mass calcium / density
Volume calcium = 44.1 grams / 1.55 g/mL
Volume calcium = 28.45 mL ≈ 28.5 mL
We need 28.5 mL of Calcium solution