Răspuns:
Explicație:
Ca(OH)2
raport de masa = r.m.
r.m.=ACa : 2AO : 2AH
=40 : 2.16 : 2
=40 : 32 : 2 se simplifica cu 2
=20 :16 :1
Compozitia procentuala prin raport de masa
se aduna partile :20 +16 +1=37
37g Ca(OH)2--------20g Ca------16g O---------1gH
100gCa(OH)21-----------x--------------y--------------z
x=100.20 :37=54,05%Ca
y=100.16 :37=43,24%O
z=100 .1 :37=2,71% H