Nerves send signals to your brain from your spinal cord. If something is burning your nerves will send a pain signal from the area of the burn to your brain through you spinal cord. Then your brain sends a signal back to the nerves that there is pain and you should avoid it. Same with internal nerves and same with touch.
A. Adding iodine
hope this helps
When two element combine to form more than one compound i hope this helps you with work have a nice day :)
I'm not entirely sure but i think it's Se2-
