Color of Iron (II) Phosphate precipitate? (1 Viewer)

[science]

Hey guys, just been consolidating my notes for identification of anions, and for PO4 i add Fe2+ which gets you Fe3(Po4)2- an insoluble ppte. However, one of my notes says this ppte is green, but after looking it up to make sure- wikipedia says its brown? What's correct?

 

[Cleverusername5321]

Okay, I could be wrong but isn't it only the cation that affects the colour (I seriously wouldn't trust myself on this)? And in that case, green would be Fe2+ and brown would be Fe3+?

Also, for identifying phosphate, don't you just add ammonia (to make the solution basic) and then barium, which produces a white ppte? (If the solution isn't basic it can also be sulfate). This is going by Conq Chem HSC, and seems to be much simpler.

 

[science]

Ah ok that makes sense.

Yeah , thats another one I've seen. Every source seems to have different identification reactions

 

[Cleverusername5321]

Ah ok that makes sense.

Yeah , thats another one I've seen. Every source seems to have different identification reactions

I think there's a problem with using iron (II) because it quickly oxidises to iron (III).

 

[faisalabdul16]

Add silver nitrate to phosphate and you'll get a yellow ppt