Electrochemistry Exercise: Normal Potential of a Reaction

AI Thread Summary
The discussion revolves around calculating the normal potential for the reaction HA(aq) + e- → A-(aq) + 1/2H2(g) at 25 °C, given a dissociation constant of 3.3*10-4. The calculation using the formula E° = RT/(nF)lnK yields a result of E° = -0.206V. However, the textbook answer key presents a different sign for the potential, leading to confusion. The original poster questions whether this discrepancy is due to a mistake in their calculations or a possible typo in the textbook. The conversation highlights the importance of verifying calculations and understanding the implications of reaction potentials.
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Homework Statement



Calculate the normal potential at 25 °C for the reaction:

HA(aq) + e- → A-(aq) + 1/2H2(g)

if the dissociation constant of HA is equal to 3.3*10-4

Homework Equations



ΔG° = -RTlnK ⇔ -ΔG°/nF = RT/(nF)lnK ⇔ E° = RT/(nF)lnK

The Attempt at a Solution



Just plugging in the numbers gives the answer E°=-0.206V
However, the answer key of the textbook disagrees on the sign... Am I overlooking something or is it just a typo? I can't imagine what my mistake could be...
 
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Typo for me. But I am known to be occasionally wrong.
 
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