[hartalinstalin69]

So, I have been trying to understand this reaction recently: (COOH)2 + FeSO4 → Fe(COO)2 + H2SO4
The thing I don't understand is that oxalic acid is a weak acid compared to sulphuric acid which is a strong acid.
Shouldn't it stay as it is due to this? My knowledge tells me that this reaction could happen only this way:
 Fe(COO)2 + H2SO4 (COOH)2 + FeSO4

Idk, please no hate and thanks for the answers 

[Borek]

Yes, I am not convinced reaction as written will proceed to the end. Where did you got it from?

This will be an equilibrium system. Solubility of dihydrate listed as 0.097 g per 100 mL of water suggests Ksp around 3×10^-5, without calculating exact numbers: if you just mix sulfate with oxalic acid I would expect some precipitate, but definitely not all iron will react.

Also: oxalate is a strong complexing agent, reaction equation can refer to the creation of a soluble complex.