Iodine is released when potassium iodide reacts with

Consider the following list of reagents:
Acidified $K_2Cr_2O_7$,alkaline $KMnO_4$,$CuSO_4$,$H_2O_2$,$Cl_2$,$O_3$,$FeCl_3$,$HNO_3$ and $Na_2S_2O_3$. The total number of reagents that can oxidise aqueous iodide to iodine is

Which of the following combinations of reagents does not undergo a redox reaction in an aqueous medium?

When silver nitrate is heated to red hot,what is formed?

Explain the uses of indicators in the analysis of redox reactions.

$K_2Cr_2O_7$ paper acidified with dilute $H_2SO_4$ turns green when exposed to