Na2 does not stand for anything by itself, because Na2 does not exist. Na2 would be part of a compound, such as Na2S or Na2O, in which case it means two sodium ions bonded with one sulfide ion or one oxide ion.
Diphosphonic Acid. I beleve.
Na2 is not a compound. When you see a formula containing Na2, it means the compound contains 2 Sodium ions.
The molecular formula for Sodium Nitroprusside is Na2[Fe(CN)5NO].
Na2. Co3
Na2+1O11-
O2,N2,H2,F2,Cl2,Li2,Na2
Na2[Fe(CN)5NO]·2H2O
Formula: Na2B4O7·10H2O or Na2[B4O5(OH)4]·8H2O
Sodium peroxide.
Na = +1 Na2 = Na(2) = +2
Sodium - Na2+
This is sodium sulphate.