Question: Why are toxic gasses such as chlorine gas so deadly, because I know that they are very harmful, but I was curious as to what things they to the body that make them so dangerous.

Hannah Farley answered on 19 Jun 2018:

When chlorine gas comes into contact with moist tissues (like your airways, mouth, the lining of your lungs) it creates an acid (hydrochloric acid) that damages these tissues. If you’ve seen HCl (hydrochloric acid) in the chemistry lab you’ll see that it has danger symbols on it to let people know that it’s toxic. So it basically dissolves the lining of your lungs, which is pretty grim.