Calcium hydroxide is a monoacidic base.

Show by the help of an appropriate litmus paper that the aqueous solution of ammonia is alkaline in nature. 

What is an alkali? Do basic solutions also have ${\mathrm{H}}^{+}$(aq) ions? If yes, then why are these basic? 

The salt solution which does not react with ammonium hydroxide is:

If $\mathrm{pH}$ of a solution is 13, means that it is

Explain the alkali.

The $\mathrm{pH}$ of a compound is found to be 9. The compound can be