# How can I identify ions in solutions?

May 22, 2018

Well, you would have to perform chemical tests to be sure.

#### Explanation:

Some common ions, such as halide ions, copper ions, zinc ions, and ammonium ions can be easily tested.

Halide ions will react with silver nitrate $\left(A g N {O}_{3}\right)$ to give coloured precipitates of silver halides. For example, chloride ions will react with $A g N {O}_{3}$ to give out silver chloride $\left(A g C l\right)$, which is an insoluble white precipitate.

Copper ions are usually in their $+ 2$ state, and are blue in coloured solutions. To test for them, simply add some sodium hydroxide and a blue precipitate of copper(II) hydroxide $\left(C u {\left(O H\right)}_{2}\right)$will form.

Of course, there are many other tests, and these are the basic ones.