23g Na -------1mol Na-------11 . 6,023 .10²³ e-------12 . 6,023 .10²³ n
b.
se afla nr . de moli de Li
n=m:M= 1,4 g : 7g/mol
=0,2 moli Li
1mol Li----------3 . 6,023 .10²³ e------------4 . 6,023 .10²³ n
0,2 moli-----------------x------------------------------y
x=0,2 .3 . 6,023 .10²³ e =
y= 0,2 . 4 .6,023 .10²³ n =
c.
4kg=4000g Ca
n= 4000g : 40g/moli=100moli Ca
1moli Ca -----------20 .6,023 .10²³ e-------------20. 6,023 .10²³ n
100 moli ----------------x-----------------------------------y
x=100. 20 .6,023.10²³ e =
y= 100. 20 .6,023 .10²³ n=
d.
5kmoli=5000 moli
1mol He---------2. 6,023 .10²³ e--------------2. 6,023.10²³ n
5000 moli He--------------x-------------------------------y
x=5000 . 2 .6,023 .10 ²³ e=
y=5000.2.6,023.10²³ n =