Ferroxyl Indicator Composition: Simple, Useful Corrosion Mix

Summary for ferroxyl indicator composition Discussion

Ferroxyl indicator composition is given in the thread as a simple saline mix for corrosion experiments. Lynn Tan asked for the amounts needed to add a few drops to sodium chloride solution and watch anodic areas turn blue as ferrous ions appear. Nygel Tan replied with a practical recipe: sodium chloride 20 g/L, potassium ferricyanide 2 g/L, and phenolphthalein solution 2 cc/L. The exchange is framed as a student corrosion demonstration rather than a formal analytical method. A later question from Tammie T. asks whether any indicator besides potassium hexacyanoferrate could be used to detect Fe3+ in a metal corrosion experiment, but no answer is shown in the excerpt. The main usable takeaway is the specific ferroxyl indicator formulation supplied by Nygel Tan.

Q. Hi,

I hope you are able to solve my question: I would to find out the AMOUNT OF CHEMICAL CONTENTS in Ferroxyl Indicator (a saline solution containing potassium ferricyanide ⇦ on

eBay

orsit

Amazon

[affil link] and phenolphthalein

on

eBay &

Amazon [affil link]
).

I am going to do an experiment on corrosion of materials. One of the requirements is to carry out an experiment to watch the changes by adding to the sodium chloride solution a few drops of ferroxyl indicator.

After that I will observe the anodic area turn blue showing the ferrous ion (i.e. corrosion) and so on and so forth.

Thank you & regards,

Lynn Tan
student – Singapore
2004


A. For my experiment, my ferroxyl indicator is made up of:

Sodium Chloride 20g/L
potassium ferricyanide ⇦ on

eBay

orsit

Amazon

[affil link] 2g/L
Phenolphtalein solution 2cc/L

Hope this helps

NYGEL TAN
– Singapore
2004

Q. Hi I’m a secondary school student and I’ve got a question to ask:
I would like to know what indicator (apart from potassium hexacyanoferrate) could I use in the experiment of the corrosion of metal to detect Fe3?
Thank you.

Tammie T.
Student – Malaysia
2007