* Base: A substance that can accept a proton (H+) or donate a hydroxide ion (OH-) in a chemical reaction.
* Alkali: A type of base that dissolves in water to produce a solution with a pH greater than 7.
Examples of alkalis include:
* Sodium hydroxide (NaOH): Commonly known as lye, used in soap making and drain cleaners.
* Potassium hydroxide (KOH): Used in making liquid soap, fertilizers, and batteries.
* Calcium hydroxide (Ca(OH)2): Found in limewater and used to adjust the pH of soil.
* Ammonia (NH3): A weak base that dissolves in water to form ammonium hydroxide (NH4OH).
Key properties of alkalis:
* They have a bitter taste.
* They feel slippery to the touch.
* They turn red litmus paper blue.
* They react with acids to form salt and water.
Note: Not all bases are alkalis. Some bases, like magnesium oxide (MgO), are insoluble in water.
