Potassium chromate solution is added to an aqueous solution of metal chloride. The yellow precipitate thus obtained is insoluble in acetic acid. The precipitate is subjected to a flame test the colour of the flame is:

An aqueous solution of a metal chloride is mixed with potassium chromate solution. The resulting precipitates are not soluble in acetic acid. 
These are put through a flame test;
The flame is apple green in colour.
Chromium is produced as $\mathrm{Cu}{\left({\mathrm{BO}}_2\right)}_3$ when borax beads are heated in an oxidising flame.
In both hot and cold oxidising flames, it produces green colour.