The molar mass of CaF2 can be calculated as follows:
M(CaF2) = M(Ca) + M(F) x 2
= 40.08 g/mol + 18.998 g/mol x 2
= 78.076 g/mol
Therefore, one mole of CaF2 has a mass of 78.076 g.
To determine the amount of F in 425 g of CaF2, we need to first calculate the number of moles of CaF2 in 425 g:
n(CaF2) = m(CaF2) / M(CaF2) = 425 g / 78.076 g/mol = 5.44 mol
Next, we can use the stoichiometry of the formula CaF2 to determine the number of moles of F in 5.44 mol of CaF2:
1 mol of CaF2 contains 2 moles of F
Therefore, n(F) = 2 x n(CaF2) = 2 x 5.44 mol = 10.88 mol
Finally, we can convert the number of moles of F to grams of F by multiplying by the molar mass of F:
m(F) = n(F) x M(F) = 10.88 mol x 18.998 g/mol = 206.98 g
Therefore, there are 206.98 grams of F in 425 g of CaF2.