Because, "alkali" is basically the term for a base in a liquid form, whereas a base is an alkali in a liquid or gas form so cannot be called an alkali because it is not liquid. A base which is...
Bases have a pH above 7. These are of two types. The one which is soluble is called ALKALIES. The one which are insoluble are called INSOLUBLE BASE. Not all bases are soluble but only some of them...