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Which of the follow ing on the addition ...

Which of the follow ing on the addition will cause deep red colour to disappeared ?
`underset("pale yellow")(Fe_(aq)^(3+)) + underset("colourless")(SCN_(aq)^(-)) hArr underset("deep red")([ Fe (SCN) ]_(aq)^(2+))`

A

`AgNO_(3)`

B

`HgCl_(2)`

C

`H_(2)C_(2)O_(4)`

D

`H_(2)O`

Text Solution

Verified by Experts

The correct Answer is:
A, B, C
a) `Ag^(+)` ion removes `SCN^(-)`
`Ag^(+)` ion removes `SCN^(-) to AgCNS darr`
b) `Hg^(2+)` ion remove `SCN^(-)`
`Hg^(2+) 2SCN^(-) to Hg(CNS)_(2) darr`
c) `C_(2)O_(4)^(2-)` ion remove `Fe^(3+)` by complex formation
`Fe^(3+)+3 C_(2)O_(4)^(2-) to [Fe(C_(2)O_(4))_(3)]^(3-)` complex soluble
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