What chemicals are in smoke?

Numerous: Smoke contains organic molecules, inorganic ash and acidic residues. There are hundreds of different compounds. There are few that your body can tolerate and many are lethal to the cells of your lung and wind passages. They are the basis of why smoking is so dangerous.

Lots, and lotsa bad.: The Internet has lists of cigarette ingredients, some of which list over 599 ingredients and as many as 7000 chemicals. You'll be surprised to see what's in a cigarette. At least 40 are carcinogenic. http://www.tricountycessation.org/tobaccofacts/Cigarette-Ingredients.html