Base and Alkali

-Base is defined as a substance that can neutralise acids to form salt and water.

-A base which is soluble in water is known as an alkali

-An alkali is a substance that ionises in water to produce hydroxide ions,OH-.

For example,sodium hydroxide,NaOH is an alkali as it dissociates in water to form hydroxide ions in the following manner:

NaOH(s)>Na+(aq) + OH-(aq)

- An alkali has the following physical properties:

*bitter taste

*slippery feel

*pH higher than 7

*turns red litmus paper blue

*conducts electricity