The quinhydrone electrode `(Q,H^(o+)|H^(2)Q)` is used in conjunction with a saturated calomel electrode, as represented below`:` `EMF_(cell)=0.264V` at `30^(@)C`. Calculate the `pH` of unknown solution at this temperature. Given `:E_(calomel)=0.24V` and `E^(c-)._(2H^(o+),Q|H_(2)Q)=0.7V`

The quinhydrone electrode `(Q,H^(o+)|H^(2)Q)` is used in conjunction w

1.	The quinhydrone electrode `(Q,H^(o+)\|H^(2)Q)` is used in conjunction with a saturated calomel electrode, as represented below`:` `EMF_(cell)=0.264V` at `30^(@)C`. Calculate the `pH` of unknown solution at this temperature. Given `:E_(calomel)=0.24V` and `E^(c-)._(2H^(o+),Q\|H_(2)Q)=0.7V`
Answer» `(` Note that the value `2.303(RT)/(F)`at`30^(@)C=0.06)` `E_(S C E )=0.242V` `E_(qui nhydron e)=E^(c-)._(qui n hydron e )-0.06pH(`at`30^(@)C)` `:. E_(cell)=E_(RHS)-E_(LHS)=E_(qui n hydron e)-E_(SCE)` `0.264V=0.7-0.06pH-0.24(` at` 30^(@)C)` `:. pH=(0.7-0.24-0.264)/(0.06)=3.266~~3.27`

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The quinhydrone electrode `(Q,H^(o+)|H^(2)Q)` is used in conjunction with a saturated calomel electrode, as represented below`:` `EMF_(cell)=0.264V` at `30^(@)C`. Calculate the `pH` of unknown solution at this temperature. Given `:E_(calomel)=0.24V` and `E^(c-)._(2H^(o+),Q|H_(2)Q)=0.7V`

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