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 crisis in the Democratic Republic of the Congo the water sector. The water crisis in the DRC is impacting especially the most vulnerable groups of society, namely women and children living in poor, unplanned peri-urban areas and remote rural areas. In crowded urban centres, households often have to purchase their water at inflated prices due to high demand and supply scarcity, while unimproved water sources are used for drinking water supply in rural areas, posing significant health risks. Typically, women and children assume the main responsibility of providing water supplies for their families. Water supply scarcity transforms this process into a highly laborious and time-consuming activity, which decreases