A petrochemical is any chemical made from petroleum or natural gas. The refining of petroleum is undertaken on a large scale not only for the fuels obtained (gasoline (petrol), paraffin, fuel oil, and natural gas) but also for the wide range of chemicals that can be derived. These chemicals include the common alkanes (paraffins) and alkenes (olefins), benzene, toluene and naphthalene, plus the inorganic substances carbon black, sulfur, ammonia, and hydrogen peroxide. Polymers, detergents, solvents, and nitrogen fertilizers are major products.