sulfur dioxide and nitrogen oxides (which, as mentioned before, come from cars, electric utility plants and industrial facilities) get emitted into the air. Once there, they react with water and oxygen (which, luckily for those of us who breathe air, are both quite abundant!) and produce sulfuric acid and nitric acid. These compou Once these compounds are formed, they can hang out in the atmosphere for really long periods of time (sometimes days or weeks). Sometimes they linger in the air but take a trip, traveling more than a thousand miles! When they do come back to Earth, they can come down in many forms - rain, snow, fog and even as dry dust particles.nds have a very low pH and are, therefore, very acidic.