H 2 O + H 2 O = − lg [ H 3 O + ] {\displaystyle {H_{2}O+H_{2}O=-\lg[H_{3}O^{+}]\!}} ⇌ H 3 O + + O H − {\displaystyle {H_{3}O^{+}+OH^{-}\!}}
![{\displaystyle \mathrm {pH=-\log _{10}[H_{3}O^{+}]=-\lg[H_{3}O^{+}]\!} }](https://wikimedia.org/api/rest_v1/media/math/render/svg/e631ef0ac4b1ea1f6a8a2dd2037bf29c4dad68dd)
![{\displaystyle {H_{2}O+H_{2}O=-\lg[H_{3}O^{+}]\!}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/a9d5262f09fc59b7baa20300a0304267189b3c9e)
