University of Edinburgh

BSL Chemistry Glossary - acid - definition and examples

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Definition: All of these substances can be found in our homes. All are acidic. We use the pH scale to describe the strength of acids and alkalis. It runs from 0 to 14. All acids have a pH of less than 7. These household substances have different pH numbers from 1 to 5 and beyond to 7 (which is neutral). The car battery has a very strong acid (pH 1) and it is very corrosive. It is dangerous as if you put your finger in the acid, your skin will burn and your finger could even dissolve if left in long enough. However, it is safer to put your finger in tomato sauce as it has a weaker acid (pH 5). If you try to taste these fruits, it will taste sour because they contain an acid. These substances are grouped according to their pH values – pH 1, 2, 3, 4 and 5. Lemon is sourer than the apple because lemon has a stronger acid.

laboratory acids

household acids