3 ms·
I thought pH = -log[H+]? where [H+] is the molarity of the hydrogen ion? That doesn't involve water in the definition... what is the definition you're referring
by wfunction 9y ago
I thought pH = -log[H+]? where [H+] is the molarity of the hydrogen ion? That doesn't involve water in the definition... what is the definition you're referring to?
Edit regarding your reply asserting water is necessary (I can't reply now due to throttling):
What about all the acid/base reactions that don't involve water? You can't ascribe any pH to either of them in that case?
- Pulcinella 9y ago[H+] is shorthand for [H3O+]. H3O+ (hydronium ion) requires water plus a hydrogen ion from the acid. There aren't actually free H+ ions floating around. They are all attached to water molecules.
- yogipatel 9y agoThat's the definition of p[H]. The definition of the "real" pH is the -log of H+ activity. H+ activity is the concentration of H+ * a coefficient. In practice, the coefficient is considered to be 1, however there are cases (such as extreme concentrations) when that approximation isn't valid.
- Pulcinella 9y agoAh yes I had forgotten about activity. :)