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chemistry question

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perrychan527:
State what u would see as iron(II) ions in solution are titrated with potassium manganate(VII). How would u detect the endpoint of the titration?(3)

Ans: purple colour of MnO4- lost (1)
endpoint when yellow/ colourless solution (1)
becomes permanently pink (1)

I dont know what does it mean. I know purple is lost as MnO4- is reduced to Mn2+. The yellow is due to Fe3+, but why permanently pink????
Thank guys  ;)

cashem'up:
this is because when the color is permanently pink it shows that all the Fe has reacted and the MnO4 reduced and that the extra drop of KMNo4 goes to show that the reaction is complete as this drop is not reduced due to the lack of color change.
hope it helps
 ;)

nid404:
Paper?

any particular indicator mentioned?

perrychan527:
i got some of ur pt. What did u mean is that the extra drop of MnO4- is purple itself, but when it goes to a large amount of colourless solution, solution become pink?

perrychan527:
no indicator

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