To find the molar mass of calcium fluoride (CaF2), we need to add the molar masses of calcium (Ca) and two fluorine (F) atoms.
The atomic mass of calcium is approximately 40.08 g/mol, and the atomic mass of fluorine is about 19.00 g/mol. Since there are two fluorine atoms in calcium fluoride, we calculate the total mass of fluorine as follows:
Total mass of fluorine: 2 × 19.00 g/mol = 38.00 g/mol
Now, we add the mass of calcium to the total mass of fluorine:
Molar mass of CaF2: 40.08 g/mol (Ca) + 38.00 g/mol (F) = 78.08 g/mol
Therefore, the molar mass of CaF2 is approximately 78.1 g/mol. Thus, the correct answer is b) 78.1 g/mol.