Răspuns:
Explicație:
1.
0,06 kg= 50 g K
n= 50g : 39g/moli=1,28 moli K
1molK-------6,022.10²³atomi K
1,28 moli-------------x
x= 1,28 . 6,022.10²³=7,70816 .10²³atomi K
2.
1mol Na----------6,022.10²³atomi Na
2,02 moli----------------y
y= 2,02 .6,022.10²³=12,16444 .10²³atomi K
3.
0,075kg= 75g Be
n= 75g : 9g/moli=8,33 moli Be
