Final answer:
Calculate the moles of CaF2 using its molar mass, then use the mole ratio to find moles of fluorine, and finally convert to grams of fluorine using fluorine's atomic mass.
Step-by-step explanation:
To calculate the mass of fluorine in a given mass of calcium fluoride (CaF2), we need to use stoichiometry and the molar masses of the elements involved. The molar mass of CaF2 is 78.08 g/mol, which comprises the molar mass of calcium (Ca) at 40.08 g/mol and fluorine (F) at 19.00 g/mol for each atom, totaling 38.00 g/mol for both fluorine atoms.
The first step is to calculate the number of moles of CaF2 in 275 g of the compound:
Number of moles = mass (g) / molar mass (g/mol) = 275 g / 78.08 g/mol
Next, we use the mole ratio from the chemical formula (1 mole of CaF2 contains 2 moles of F) to find the moles of fluorine. Then, we convert moles of fluorine to grams by multiplying by the molar mass of fluorine (19.00 g/mol).