In acid-base chemistry, we use the pH scale to measure the acidity or basicity of a solution. The scale ranges from 0 (most acidic) to 14 (most basic), with 7 being neutral. Acids have a pH less than 7, while bases have a pH greater than 7. The strength of an acid or base is also determined by its pH value.

Acid-base reactions involve the transfer of protons (H+) from an acid to a base. When an acid donates a proton to a base, it forms its conjugate base, while the base becomes its conjugate acid. This process is known as acid-base conjugation. The strength of an acid or base is measured by its ability to donate or accept protons, also known as its acid dissociation constant (Ka) or base dissociation constant (Kb).

Understanding acid-base chemistry is important in many fields, including biochemistry, medicine, and environmental science.