Răspuns:
Explicație:
1.
a. m= n . M
0,35kmoli= 350 moli Na
m= 350moli . 23g/moli= 8050 g Na
b. m= 5,5moli. 27g/moli= 148,5 g Al
2.
0,405 kmoli= 405 moli Cr
12moli V
3.
a.
1mol Ni----------6,022.10²³ atomi Ni
3moli Ni---------------x
x= 3 . 6,022.10²³=18,066.10²³atomi Ni
b.
n= 70g : 137g/moli=0,51 moli Ba
1mol Ba---------------6,022.10²³atomi Ba
0,51moli-------------------x
x= 0,51 . 6,022.10²³=3,07122.10²³atomi Ba