To solve this problem, we can use the formula:
moles of solute (CaF2) = concentration (in moles per liter) x volume (in liters)
First, we can calculate the number of moles of CaF2 in the solution:
moles of CaF2 = concentration x volume
moles of CaF2 = 0.15 mol/L x 1.25 L
moles of CaF2 = 0.1875 mol
Next, we can use the molar mass of CaF2 to convert moles to grams:
mass of CaF2 = moles of CaF2 x molar mass of CaF2
mass of CaF2 = 0.1875 mol x 78.08 g/mol
mass of CaF2 = 14.64 g
Therefore, there are 14.64 grams of CaF2 present in 1.25 L of a 0.15 M solution of CaF2.