What is the pH of neutral water at 30 degC?

Everyone knows that water has pH = 7....or does it?

The traditional "7" value is only true at 25oC.

It comes from Kw having a value of 1 x 10-14 mol2dm-6.

Think about the meaning of Kw, think about how equilibrium constants change with temperature.

Discuss this with your friends. I will add more clues and an answer at a later date.

Hint:  Try to think logically. If you don't know one step of the calculation, you can always say something like, "If we assume this, then we can deduce that." In this way, if you find out (or are told) extra information, you can mkae sensible modifications to your calculation.  Good luck! 

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