Bases are chemical substances that increase the pH of a solution when dissolved in water. Strong bases, including sodium hydroxide and potassium hydroxide, dissociate completely in water and increase the pH to between 10 and 14. Weak bases do not dissociate completely and have less drastic effects on pH.
Baking soda and baking powder are leavening agents that produce gas due to the reaction of an acid and a base. These gas bubbles give foods a lighter texture. Baking soda is a weak base and has the characteristic bitter taste associated with bases. When recipes use baking soda, they generally include other ingredients, such as milk, to counteract the flavor of the base. Baking powder includes baking soda and cream of tarter, an acid. It has a neutral impact on the flavor of the food.
Bases feel slippery when dissolved in water; laundry detergent is a common example. They lower the surface tension of water, making it more effective at cleaning laundry.
Bases neutralize acids. When the stomach produces too much acid, an individual may experience heartburn. Antacids are bases that help raise the pH of the stomach acid to closer to neutral and reduce the burn. Magnesium hydroxide is a common base used as an antacid.