Answer:
Mass fraction for Ca is 0.52
Mass fraction for F is 0.48
Explanation:
Molecular formula for fluorite is CaF₂
Molar mass: 78.08 g/mol
1 mol of CaF₂ has 1 mol of Ca and 2 moles of F
1 mol of Ca = 40.08 g
2 mol of F = 38 g
We verify the relation by rules of three:
78.08 g of CaF₂ have 40.08 g of Ca
2.76 g of CaF₂ must have (2.76 g . 40.08g ) / 78.08 g = 1.42 g
So, 78.08 g of CaF₂ have 38 g of F
2.76 g of CaF₂ must have (2.76 . 38 ) / 78.08 g = 1.34 g
Mass fraction = Grams of Ca / Total grams or Grams of F / Total grams
1.42 g / 2.76 g = 0.52
1.34 g / 2.76 g = 0.48