Properties of water equal to that of the hydrogen ion (), which gives a pH of 7 at 25 °C. Action of water on rock over long periods of time typically leads to weathering and water erosion, physical processes that convert solid rocks and minerals into soil and sediment, but under some conditions chemical reactions with water occur as well, resulting in metasomatism or mineral hydration, a type of chemical alteration of a rock which produces clay minerals. It also occurs when Portland cement hardens. Water ice can form clathrate compounds, known as clathrate hydrates, with a variety of small molecules that can
Water contamination in Lawrence and Morgan Counties, Alabama water from the United States' utilities, where researchers had found traces of chemicals in the water of areas including Lawrence County and Morgan County, Alabama. Although there is minimal information on the long-term effects of the contaminated water, researchers discovered that a fluorinated compound called Perfluorooctanoic acid was in the water sample. This chemical compound has been linked to many other health problems, such as thyroid disease, kidney cancer, and pregnancy-induced hypertension. Many Alabama residents have been suffering from contaminated water that can cause cancer, congenital disabilities for women of childbearing age, and developmental problems for children. EPA health advisories