The two elements involved, iron and chlorine, each change oxidation state; iron from +2 to +3, chlorine from 0 to -1. There are then effectively two half-reactions occurring. These changes can be represented in formulas by inserting appropriate electrons into each half-reaction: Fe2+ → Fe3+ + e.
The electrons are supplied by the species getting oxidized. They move from anode to the cathode in the external circuit. The external battery supplies the electrons. They enter through the cathode and come out through the anode
because the 2nd shell is not complete which is suppose to be 8 and since oxygen is 8 it first shell is 2 which is complete and the second shell which is 6 is not complete because we all know that 2+6=8 but the standard shell is
The wistle is coming from all the chemicals including the fire you use to light the firework and a chemcial reaction is occuring which is the sound that is made because of this
