In Water, What Do Bases Form?

In water, bases form alkalis. Examples of bases that form alkalis in water are sodium hydroxide and ammonia. Some bases, such as copper oxide, are not soluble in water.

Alkalis have a pH value that is greater than 7. The more powerful the alkali, the greater the pH value is. When a red litmus paper is dipped into an alkali, it turns the paper blue. A weak alkali such as ammonia turns a universal indicator paper bluish-green and gives a pH reading of 10 to 11. A strong alkali such as sodium hydroxide turns the paper dark purple or blue, and it gives a pH reading of 13 to 14.