CaF2 = flourura de calciu
1.
miu = Aca + 2xAcl = 40 + 2x35,5 = 111 g/mol
111 g CaF2 ..... 40 g Ca .... 71 g Cl
100% (100g) .... a% ........... b%
=> a = 40x100/111 = 36,04% Ca
restul 100-36,04 = 63,96% F
2.
Ca : F = 40 : 71
3.
Ca : F = 1 : 2
4.
miu = 111 g/mol
=>
1 mol .......... 111 g