Question

50p!!!
Calculeaza nr de ioni existenti in 12,4 g oxid de sodiu

Answer 1

M Na2O = 62 g/mol
NA = 6.023 x 10^23 particule / mol
particule = atomi, molecule, ioni.

m Na2O = 12.4 g
n Na2O = m/M = 12.4 / 62 = 0.2 mol Na2O

1 mol Na2O dupa disociere formeaza: 2 mol Na(+) si 1 mol O(2-) = 3 moli de ioni

asadar:
1 mol Na2O disociat .... 3 x NA
0.2 mol Na2O disociat ..a

a = 0.2 x 3 x NA 
a=  0.2 x 3 x 6.023 x 10^23 = 3.6138 x 10^23  ioni