Introduction
When we need to find out if an ion is present in a solution, we need to know which are the substances containing those ions that are insoluble, so we can produce the precipitate.
In the case of group 1 ions, Na+, K+, etc., form all soluble compounds, so there is not possibility of producing any precipitation.
For these elements and some more, we use a FLAME TEST.
TEST FOR AMMONIUM IONS<