Răspuns:
Explicație:
1.
n= m : M
m= n . M
m= 10kmoli . 23kg/kmoli= 230 kg Na
2.
160kg= 160000g Ca
n= 160000g: 40g/moli= 4000 moli Ca
1mol Ca ---------6,022.10²³atomi Ca
4000 moli Ca---------------x
x= 4000 .6,022.10²³ =24088 .10²³atomi Ca
3.
12,044.10 la 24= 120,44.10²³
n= 120,44 .10²³ : 6,022.10²³ = 2moli de atomi N
II.
K Z=19 ------> 19e, 19p , 20n
A=39
K-2e
L-8e
M-8e perioada 4, grupa I a
N -1e
-sarcina nucleara + 19
Izotopi - are 24 de izotopi
- cei mai importanti : K Z= 19 A=39
K Z=19 A= 40
K Z=19 A= 41
