Question

Cati electroni se gasesc in 14,2 g Clor?

Answer 1

1 mol Ca.............35g 
x.........................14,2g

x=14,2/35=0,40 moli

1mol.................6,023 * $10^{23}$  atomi
0,40 moli...................x

x=0,40* 6,023 * $10^{23}$=2,409 * $10^{23}$ atomi 

nr de e =40* 2,409* $10^{23}$