Question

define alkalies and give an example

Answer 1

Alkali salts are soluble hydroxides of alkali metals and alkaline earth metals, of which common examples are: Sodium hydroxide – often called "caustic soda" Potassium hydroxide – commonly called "caustic potash" Lye – generic term for either of the previous two or even for a mixture.

Answer 2

a compound with particular chemical properties including turning litmus blue and neutralizing or effervescing with acids; typically, a caustic or corrosive substance of this kind such as lime or soda.
examples-Sodium hydroxide – often called "caustic soda" Potassium hydroxide – commonly called "caustic potash" Lye – generic term for either of the previous two or even for a mixture.