* Vinegar: Acetic acid, a mild acid, is the main component of vinegar. It is commonly used in cooking and as a cleaning agent.

* Lemon juice: Citric acid, a weak organic acid, is found in high concentrations in lemon juice. It is used as a flavoring in food and drinks and can be used to clean metal surfaces.

* Baking powder: Sodium acid pyrophosphate, a leavening agent, is the main acidic component of baking powder. It is used in baking to create carbon dioxide gas, which makes baked goods rise.

* Aspirin: Acetylsalicylic acid, the active ingredient in aspirin, is a mild acid used as a pain reliever and fever reducer.

* Hydrochloric acid: Muriatic acid, a concentrated form of hydrochloric acid, is used for cleaning tiles, grout, and other surfaces. It is a strong acid and should be used with caution.

Alkalis:

* Baking soda: Sodium bicarbonate, a base, is the main component of baking soda. It is commonly used as a leavening agent in baking and can also be used as a cleaning agent.

* Ammonia: Ammonia, a strong alkali, is used as a cleaning agent for surfaces such as glass and tiles. It is also used in some household cleaning products.

* Lye: Sodium hydroxide, a strong alkali, is used in making soap and as a drain cleaner. It is a caustic substance and should be used with caution.

* Toothpaste: Many toothpastes contain alkalis, such as sodium bicarbonate or sodium hydroxide, to help neutralize acids in the mouth and whiten teeth.

* Detergents: Many detergents, such as laundry detergent and dishwashing liquid, contain alkalis to help remove dirt and grime.