What method would best allow these three different scientists to demonstrate their concepts?

Ionic compounds are made of ions, and yet the overall charge of an ionic compound is neutral. why?

In the following redox reaction which is the oxidizing agent and which is the reducing agent? alcl3 + na nacl + al oxidizing agent = reducing agent =

At stp, which substance is the best conductor of electricity? a. nitrogen b. neon c. sulfur d. silver