Acid and Base | Acids, Bases & pH | Video for Kids

Acids and bases are two distinct types of chemicals. Most liquids are either acidic or basic, depending on the type of ions they contain. Liquids with many hydrogen ions are acids, while those with many hydroxide ions are bases.

Scientists use the pH scale, a chemical detector for hydronium and hydrogen ions, to determine how acidic or basic a liquid is. The pH scale ranges from 0 to 14. Acids have a pH from 0 to 7 (0 being the strongest acid), and bases have a pH from 7 to 14 (14 being the strongest base). A liquid with a pH of 7 is neutral.

Strong acids dissociate 100% into ions, while weak acids do not. Many acids and bases are found in nature, like boric acid in insecticides or hydrochloric acid. Citrus fruits like lemons, oranges, and grapes contain citric acid, which gives them their sour taste.

Antacids (bases like sodium bicarbonate and calcium carbonate) neutralize stomach acids. The stomach uses hydrochloric acid for digestion and to kill bacteria. Lactic acid is produced by muscles during exercise. Bases feel slippery and are used in cleaners, such as sodium hydroxide. Common household items containing bases include baking soda, drain cleaner, washing powder, and toothpaste. Common household items containing acids include yogurt, vinegar, lemon juice, and batteries.