Burning of non-metals does not directly cause acid rain. Acid rain is primarily caused by the burning of fossil fuels, such as coal and oil, which release sulfur dioxide and nitrogen oxides into the atmosphere. These compounds react with water vapor and oxygen to form sulfuric and nitric acids, which fall to the ground as acid rain. Non-metals such as chlorine, fluorine, and bromine can contribute to the formation of acid rain when they react with atmospheric moisture, but their impact is generally far less significant compared to sulfur dioxide and nitrogen oxides.