The compound which is added to table salt for maintaining proper health is

When chlorine gas is passed through an aqueous solution of a potassium halide in the presence of chloroform,a violet colouration is obtained. On passing more of chlorine water,the violet colour disappears and the solution becomes colourless. This test confirms the presence of ........... in the aqueous solution.

Identify the incorrect statement among the following.

The reaction of concentrated $HNO_3$ with iodine produces ....

The element exhibiting the most stable $+2$ oxidation state among the following is

The property which is not true about Fluorine is,