| A | B |
| acid | a with a pH of less than 7 |
| base | a substance that can react with acids and neutralise them to make a salt and water |
| alkali | a base that dissolves in water |
| pH scale | a scale 0 to 14 that is used to measure how acidic or alkaline a solution is |
| neutralize (Am) / neutralise (Br) | to add an acid to an alkali or an alkali to an acid, until the solution is neither acidic or alkaline |
| neutralization reaction / (neutralisation) | a chemical reaction in which an acid reacts with an alkali, producing a salt |
| titration | the process of adding an acid to an alkali, or the other way round, in small amounts until the two are exactly balanced |