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Hi everyone welcome back for a gruelling 11 week term.(NSW that is) Year 12 have just completed the experiment using EDTA and Eriochrome Black T.This is the first time we have attempted this experiment.I made the solutions up as Rob suggested.The EDTA dissolved very easily,no problem.Found that the Eriochrome Black T (which stains you hands!!)did not dissolve as easily, with small granules remaining!!! The teachers didn't complain about this and the experiment was successful.But I am wondering if the Erichrome Black T should have been filtered?I made 5% with 100mls pure ethanol was this right?
Mother

//EDITED by adam. Reason: make subject topic more descriptive.

Hi Lee,

It is possible to filter the Eriochrome BT as there is times where it will not all dissolve. Filtering the solution is usually what needs to take place before using the solution.

The use of Ethanol as per the quantity i gave you is standard practice and is correct. Otherwise there is no way to have the EBT to dissolve in solution as it is non-polar..

I prepare the same solutions but as 0.1% EBT..

Just remember the EBT is a dye! When you make future solutions just filter this prior to use and store. Upon storage some of the EBT may drop out of solution, just re-filter and use accordingly.

Glad to hear it went well....

Robb..........