[chickapow]

I'm trying to work out the ratio of copper to zinc in some brass samples I have via an EDTA titration.

I've dissolved the brass in concentrated Nitric Acid (70%), which I will neutralise with a volume of (2M) NaOH.

I have a method for a EDTA titration but it is for a Nickel salt, and involves Ammonia.

I could post the full method for that if it would help, as it would be ideal to just modify this method (as I know it already works).

Obviously, if you have any other ideas as to how I could determine the quantities (one idea is a displacement reaction), then I'm open to suggestions.

[Borek]

Classic method of brass analysis calls for tin precipitation first, then electrolysis of copper, then precipitation of iron, and finally zinc determination using EDTA.

EDTA will complex everything, and making it react with just one of the metals present will be very difficult.

[chickapow]

Ok! Do you have a source for this? I'll need it for my bibliography ; )