1 si 2,va rogg,dau coroana!!!!

Răspuns:
Explicație:
I.
1. H2 SO3 acid sulfuros
2. NaOH ; 40g NaOH------16g O
100g----------------x
x= 100.16 : 40= 40% O
3.HNO2 M= 1 + 14 + 2.16= 47------> 47g/moli
1mol HNO2------> 47 g
4.Ca(NO3)2-------> 6 O
Ca(NO2)2-------> 4 O
IV
5. SO2
II.
1. c MgO
2. c
3. a 4. 6,022.10²³ = 24,088 .10²³molecule