ta quy ước Oxi hóa trị ll, Hidro hóa trị l.
NO: N- hóa trị ll
NO2: N~~~ lV
N2O3: N~~~~lll
NH3: N~~~~~lll
HCl: Cl~~~~~1
H2SO4: SO4 ~~~ ll
H3PO4: PO4~~~ lll
Ba(OH)2: Ba~~~ll ; OH ~~~l
Na2SO4: Na~~~l; SO4~~~ll
K2CO3: K~~~1; CO3~~~ll
C3(HCO3)2: C~~~ll; HCO3~~~lll
NaHPO4: Na~~~l; HPO4~~~l
"~~~" : hóa trị là...
chúc bn hk tốt.