Copper (II) fluoride contains 37.42%by mass. Calculate the mass of fluorine(in grams)contained in 55.5 g of Copper(II) Fluoride.

4 answers

37.43% by mass of WHAT?????. But you really don't need to do that.
Just use dimensional analysis and convert 55.5 g Cu(II) fluoride to fluorine.

55.5 g CuF2 x (2 moles F/1 mole CuF2) =??
Use atomic mass*2 for F and use molar mas for CuF2.
Copper (II) fluoride contains 37.42% F by mass. Use this percentage to calculate the mass of fluorine in grams contained in 24.0 g of copper (II) fluoride.
111F
15.0