Identifying Fe^2+ (2 Viewers)

[sanjeevprasad99]

does anyone know the test? i cant find it anywhere

and about pb ion flame test, all i have to know is "shouldn’t be done by students, dangerous/poisonous" ?
thanks! <O

 

[xiao1985]

2,2'-bipyridine

turns pink/orange'ish when there is Fe2+. though honestly, I don't think in HSC you need to know that.

I have also been told that KMnO4 can be used to detect Fe2+, since it decolourises at the prescence of Fe2+

Re: Pb flame test: it is correct. Flame test releases particulates of the metal into the air. If inhaled, it can be quite dangerous.

 

[sanjeevprasad99]

2,2'-bipyridine

turns pink/orange'ish when there is Fe2+. though honestly, I don't think in HSC you need to know that.

I have also been told that KMnO4 can be used to detect Fe2+, since it decolourises at the prescence of Fe2+

Re: Pb flame test: it is correct. Flame test releases particulates of the metal into the air. If inhaled, it can be quite dangerous.

thanks!
in the syllabus it says "identify fe ions" so i was like "what one, fe 2+ or fe 3+" o well, ill learn both, not hard

 

[jamesy_1988]

The best method that I am aware of for the quantitative dectection of Fe2+ is the reaction with acidified potassium permangante.

 

[Kmahal1990]

Use Sodium hydroxide solution. If a precipitate forms and its white...its Fe2+. Use permangenate to confirm. The purple colour of permangenate should decolourise rapidly if Fe2+ is present. Or you can use Atomic Absorption Spectroscopy.

 

[Forbidden.]

To identify Fe²⁺ ions you need a ferricyanide such as Potassium Ferricyanide K₃(Fe(CN)₆).

Fe²⁺ + Fe(CN)₆^3- --> Fe(Fe(CN)₆)^-

The positive test for the presence Fe²⁺ with the use of ferricyanide is a prussian blue colour.

 

[xiao1985]

alot of hydroxides are white in colour... adding OH- is rather inconclusive... permangenate is a much more affirming test.

hmmm interersting point about purssian blue.... and theoretically it should work...