Why EDTA is used in titration?

Why EDTA is used in titration?

The most common indicators in complexometric titrations are organic dyes which function by forming a colored complex with the metal ion being titrated. During the reaction, EDTA replaces the indicator to form a more stable complex with metal and when the reaction is completed the change for the color is observed.

Which type of titration is iron content?

EDTA Titration of Total Iron in Iron(II) and Iron(III) Mixtures. Application to Iron Driers.

What is titration with EDTA?

EDTA is short for ethylenediaminetetraacetic acid. For the titration, the sample solution containing the calcium and magnesium ions is reacted with an excess of EDTA. The indicator is added and remains blue as all the Ca2+ and Mg2+ ions present are complexed with the EDTA.

Why do we use EDTA titration at pH 10?

pH 10 buffer is used in EDTA titration because in EDTA Y4- is predominant, and we want Y4- to react with the metal ions that are present in the titration solution.

Why indicator is not used in kmno4 titration?

Because potassium permanganate has a deep violet colour which is highly visible to the naked eye and when one titrates it and there is a loss of colour, it is apparent. So one does not need an indicator to tell you the end point. Potassium Permanganate is an oxidizing agent, which is of deep violet colour.

What is the role of ammonia buffer in EDTA titration?

The buffer adjusts the pH to ensure that the reaction goes to completion. Explanation: A complexometric titration uses the formation of a coloured complex to indicate the endpoint. EDTA, often written as H4Y, is a common ligand in complexometric titrations.

What is the pH maintained in EDTA titration?

10
Hardness is determined by titrating with EDTA at a buffered pH of 10. Calmagite is used as an indicator.

What is called buffer solution?

From Wikipedia, the free encyclopedia. A buffer solution (more precisely, pH buffer or hydrogen ion buffer) is an aqueous solution consisting of a mixture of a weak acid and its conjugate base, or vice versa. Its pH changes very little when a small amount of strong acid or base is added to it.

How does EDTA work in a titration reaction?

In a titration, EDTA, a stronger complexing agent than the indicator, displaces the indicator form the metal ion allowing the indicator to return (through shades of violet) to a pure blue color, indicating the end of the reaction.

How is the volume of EDTA used in an experiment?

For example the Nickel content in a salt. In this experiment the indicator used is murexide indicator which binds less strongly to the Nickel ions than EDTA so when the reaction is complete (all the Nickel is used up) the volume of EDTA used can then be used to determine concentration of metal ions.

Why is erichrome black T Red in EDTA?

Because erichrome black T is an indicator for complexometric titration. It is red when it forms complexes with metal ions (Ca2+, Mg2+,…). When all metal ions are chelated by EDTA, it is blue, so you can determine the end-point of the titration.

Why is EDTA able to bind to metal ions?

This ability that EDTA possesses to bind to metal ions is due to the lone pairs of electrons in its structures so it can chelate the ions. It must be done under basic conditions so H+ are not attracted to lone pairs. As a side note EDTA has good uses in medicine for example if someone overdoses on iron tables they undergo chilation therapy.