define the term bases ....
Answers
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases and Lewis bases. All definitions agree that bases are substances which react with acids as originally proposed by G.-F. Rouelle in the mid-18th century.
Base, in chemistry, any substance that in water solution is slippery to the touch, tastes bitter, changes the colour of indicators (e.g., turns red litmus paper blue), reacts with acids to form salts, and promotes certain chemical reactions (base catalysis). Examples of bases are the hydroxides of the alkali and alkaline earth metals (sodium, calcium, etc.) and the water solutions of ammonia or its organic derivatives (amines). Such substances produce hydroxide ions (OH-) in water solutions (see Arrhenius theory).