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Hi everyone,

Been asked to make up some ferroxyl indicator and surprisingly the bible has failed me for the first time I have done this before though and remember its something like potassium ferricyanide, salt water and phenolphtalein but cant remember what concentrations... Do you brilliant people out there know???

Sassi

I have a Ferroxyl Gel, Have attached for you. Sorry it says Agar plates the Ferroxyl Gel is at the bottom. We use this to Investigate how rusting occurs.

I have two recipes:

potassium hexacyanoferrate(III):
1g of powder dissolve in 100ml water.

Add indicator to a test tube containing test soln. If Fe2+ is present, solution will turn deep blue.


2nd one is used in corrosion exp and contains agar to make a gel. Students pour is over different metals into petri dishes:

100ml hot water, 3g agar powder, 1g sodium chloride and 1ml of 0.5M hexacyanoferrate. Keep warm to prevent setting.

If you need phenolphthalein, just add 0.5g or less but we do not add that to ours.

Hope this will help
lada

Ferroxyl Gel,

Hi Iain, This may be of help to you.

Sassi the exact same thing happened to me recently..
The Labbies manual recipe didnt work.


I had run out of my last batch of indicator, which worked a treat by the way. Whipped up another lot as stated in the recipe, only to find no colour charge

So am thinking of "spiking " this current batch with more of the K cyanoferrate. Maybe bring it up to about 3 or 5 g/100ml.

Can someone please point me in the direction of the notes in the CSIS for this - maybe what page in the appendices it is on.
Maybe i'm blind..or its monday - or both~
Thanks!

As it is a mixture of things, each item needs to be looked up.

Ugh. Thanks!
I am mainly after what coloured dot it is.
Gree? Or orange?
The Chem Fx label has good info on it