Theresistance per unit length of a piece of a copper wire with circular cross-section with diameterof 1.03 mm is 2.5 x 10-4Ω/cm. concentration of free electrons is 8.4 x 1028/m3. The current densityis 2.1 x 106A/m2(Assume that the free hole concentration equal zero).

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.