Edexcel IGCSE Chemistry 复习笔记 2.7.4 Bases

What makes a base act like a base?

Bases are substances which can neutralise an acid, forming a salt and water

The term base and alkali are not the same

So, all alkalis are bases, but not all bases are alkalisA base which is water-soluble is referred to as an alkali

Alkalis have pH values of above 7

In basic (alkaline) conditions red litmus paper turns blue

Bases are usually oxides, hydroxides or carbonates of metals

The presence of the OH^- ions is what makes the aqueous solution an alkali

One unusual base is ammonia solution

When ammonia reacts with water it produces hydroxide ions

转载自savemyexam