## question 55 chapter 14

Parsia Vazirnia 2L
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### question 55 chapter 14

Hi, Im a bit confused because the values given in question 55 and what is given in the solution manual are not consistent. In the book, it is given that the standard potential is -0.42 volts for water but in the solutions manual it is written that the standard potential is -0.83V. Which value did you guys use?

Chem_Mod
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### Re: question 55 chapter 14

Hi,

For the half-reaction $2H_{2}O+2e^{-} \rightarrow H_{2} + 2OH^{-}$
At pH = 7, $E=-0.42 V$
Under standard conditions, $E^{^{o}}=-0.83 V$

Note that pH = 7 is not under standard conditions.

Hope this helps!