The mass number of iodine is 126, and its in the 53rd place in the periodic table. it has

It has 53 protons and 73 Neutrons.
(Neutrons:126-53 = 73)

Hope this helped.

-Davismr00.

This is what i found on google “according to the collision theory, the following criteria must be met in order for a chemical reaction to occur: molecules must collide with sufficient energy, known as the activation energy, so that chemical bonds can break. molecules must collide with the proper orientation.” i hope this information you.