Răspuns:
Explicație:
a.
n=m : M n=nr.moli m=masa subst. M=masa molara
m= n . M
MNaOH=23 + 16 +1= 40-------> 40 g/moli
m= 5moli . 40g/moli=200g NaOH
b.
n= m : M
MNH3=14+3=17-------> 17g/moli
n= 255g : 17g/moli= 15 moli NH3
c.
n= 36,5g: 36,5g/moli=1molHCl
1mol HCl--------> 6,023.10²³ molecule de HCl
n=109,5g : 36,5g/moli=3moli HCl
1mol HCl---------6,023.10²³molecule
3moliHCl-------------------x
x=3 . 6,023.10²³=18,069 .10²³molecule HCl
