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Determine which substance is the best re...

Determine which substance is the best reducing agent in :
`PO_(4)^(3-) (aq) +2H_(2)O (l) +2e^(-) to HPO_(3)^(2-) +3OH^(-) (aq) , E^(@)= -1.05V`
`PbO_(2) (s) +H_(2)O (l) +2e^(-) to PbO(s) +2OH^(-) (aq) , E^(@) = + 0.28V`
`IO_(3)^(-) (aq) +2H_(2)O (l) +4e^(-) to IO^(-) (aq) +4OH^(-) (aq), E^(@) = + 0.56V`

A

`HPO_(3)^(2-)`

B

`PO_(4)^(3-)`

C

`IO^(-)`

D

`IO_(3)^(-)`

Text Solution

Verified by Experts

The correct Answer is:
A
For best reducing agent, `E_("Red")^(@)` is minimum.
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