Identifying Fe^2+ (1 Viewer)

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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:p
 
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xiao1985

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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.
 
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xiao1985 said:
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

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

Kmahal1990

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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.

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

Fe2+ + Fe(CN)63- --> Fe(Fe(CN)6)-

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

xiao1985

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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...
 

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