I can help. What is wrong.
The answer is Index fossils its the only answer it could be
Nitrogen triiodide<span> is the </span>inorganic compound<span> with the formula </span>NI3<span>. It is an extremely sensitive </span>contact explosive<span>: small quantities explode with a loud, sharp snap when touched even lightly, releasing a purple cloud of iodine vapor; it can even be detonated by </span>alpha radiation. NI3<span> has a complex structural chemistry that is difficult to study because of the instability of the derivatives.</span>