pH Scale

• Acid when $pH<7$, has more $H_3{O}^{+}$
• Base when $pH>7$, has more $O{H}^{-}$
• Neutral when $pH=7$, has equal amounts
• Acids donate proton, bases receive proton
• Lone pairs make a molecule basic
• Strong acids and bases fully dissociate in $H_{2}O$
  • Higher % dissociation is stronger
• $H_{2}O$ is amphoteric, can act as acid or base
• Certain reactions are reversible if in equilibrium

Equations

• $pH=-log[H_3{O}^{+}]$, $pOH=-log[O{H}^{-}]$
• $H_3{O}^{+}=10^{-pH}$, $O{H}^{-}=10^{-pOH}$
• $[H_3{O}^{+}]\cdot [O{H}^{-}]=10^{-14}$, $pH+pOH=14$

Example

• $H{C}_2{H}_3{O}_2+H_{2}O\rightleftharpoons H_3{O}^{+}+C_2{H}_3{O}_2^{-}$

• $K_a=1.45\cdot 10^{-5}=\frac{x^2}{1.2-x}$
• $x_1=4.1\cdot 10^{-3}$