Ethyl alcohol (C6H5OH) is the addictive substance.

Chemical Receptors

NO.

No, unless added to some chemicals and other addicting substances

No, not all controlled substances are addictive. Substances can offer a number of other risks, aside from addiction. For example, there are psychoactive chemicals such as LSD which are not addictive but which can cause temporary, or sometimes permanent insanity, and which are also capable of killing you if you take an overdose. Marijuana is not addictive but it is habit forming, which is kind of like addiction but not as severe. There are many other examples.