The SHE Voltage Equals Zero Convention

More importantly, note that the convention is successful at having the SHE voltage cancel out, no matter how we consider the cell reaction. Naturally, as it always cancels out, it makes no difference what its voltage is. If we arbitrarily assign a voltage of zero volts to the SHE, then instead of writing 

As we saw in the previous chapter, this same convention is the one required to effect an equivalent simplification in the definitions of single-ion properties, and these reasons are sufficient to ensure its universal adoption. Its use is acceptable as long as one realizes that it is quite unnecessary to the workings of thermodynamics. 

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