Fresh turnings of iron are an example. Calcium oxide or quicklime is a well-known example of a material that produces heat by reacting with water. In former days quicklime was made from seashells. Transportation of the product was often by boat and fires were sometimes caused by accidental wetting. Quicklime itself does not burn, but it produces sufficient heat to ignite nearby combustibles.
Alkali metals react violently with water and produce heat and hydrogen gas that flames easily.
Sulphuric acid and other concentrated inorganic acids in contact with water produce a great deal of heat. When sulphuric acid is in contact with an organic substance, the acid decomposes the substance and ignition may result. Cellulose nitrate used in celluloid and gunpowder decomposes with aging. The accumulation of decomposition products and heat accelerates further decomposition so that ignition can occur. The decomposition reaction does not require oxygen.