Mass of caf2 = 235 g
Molar Mass of Caf2 = 78.07 g/mol
Number of mole for Caf2 = 225g x 1 mole / 78.07
= 2.88 Mole
Caf2 = 2F
2.88 mol Caf2 x 2 Mol f / Mole Caf2 = 5.76 Mole F
Mass of F = 5.76 x 19.0 ( Mass number of F )
= 110g
so F = 110g in 235g of Cafs
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