SULFUR
Sulfur is a solid that when burnt produces two colourless gases: sulfur dioxide (SO2) and sulfur trioxide (SO3). The gas SO2 is strongly acidic, while the gas SO3 is slightly basic. When SO3 is dissolved in water, it forms a solution called sulfuric acid, which is a strong acid. SO2 is also a corrosive gas that can be harmful to humans and the environment. It is often produced as a byproduct of industrial processes, such as the burning of fossil fuels and the production of sulfuric acid.
Hope This Helps You!