Răspuns:
Explicație:
a.
MNaOH= 23 +16 +1= 40--------> 40g/moli
40g NaOH----------16g O
160g NaOH----------xg O
x= 160. 16g : 40=64 g O
b.
MCa(OH)2= 40 + 2.16 +2= 74-------> 74g/moli
74g Ca(OH)2-------------32g O
222g Ca(OH)2-------------y
y= 222. 32 : 74=96 g O
