Definition of $pH$ and $pOH$

Tutorial 4

Ionization of water, pH and pOH definition $ [\; ] $ Denotes molarity = concentration in mole per liter $ H_3O^+ $ is the hydronium ion $ OH^- $ is the hydroxide ion Ionization of water $ 2H_2O $ $ \leftrightarrows $ $H_3O^+ $ $ + $ $OH^- $ $ [H_3O^+] [OH^-] $ $ = $ $ 10^{-14} $ $ = $ $ K_e $ This relationship is valid both for pure water and for any dilute aqueous solution STP Definition of pH $pH$ $=$ $-log[H_3O^+]$ so: $[H_3O^+]$ $=$ $10^{-pH}$ Definition of pOH $pOH$ $=$ $-log[OH^-]$ so: $[OH^-]$ $=$ $10^{-pOH}$ Relation between pH and pOH $pOH$ $+$ $pOH$ $=$ $14$ This relationship holds for both pure water and any dilute aqueous solution STP

What is the correct relationship between $[H^+]$ and $[OH^-]$ ($K_e$ $=$ $10^{-14}$)?

a) $[H^+]$ $+$ $[OH^-]$ $=$ $K_e$ b) $[H^+]$ $+$ $[OH^-]$ $=$ $14$ c) $[H^+]\cdot[OH^-]$ $=$ $K_e$ d) $\frac{[H^+]}{[OH^-]}$ $=$ $K_e$

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