In chemistry, bases are substances that have a pH greater than 7. They are the opposite of acids, which have a pH lower than 7. Bases are also known as alkaline substances. They have a bitter taste and are slippery to the touch. Some common examples of bases include sodium hydroxide (NaOH), potassium hydroxide (KOH), and ammonia (NH3).
Many bases are also good conductors of electricity when dissolved in water, as they produce hydroxide ions (OH-) which allow the flow of electric current.