Water of crystallization degree of hydration can be critical to the resulting chemical properties. For example, anhydrous RhCl is not soluble in water and is relatively useless in organometallic chemistry whereas RhCl•3HO is versatile. Similarly, hydrated AlCl is a poor Lewis acid and thus inactive as a catalyst for Friedel-Crafts reactions. Samples of AlCl must therefore be protected from atmospheric moisture to preclude the formation of hydrates. Crystals of hydrated copper(II) sulfate consist of [Cu(HO)] centers linked to SO ions. Copper is surrounded by six oxygen atoms, provided by two different sulfate groups and four molecules of water. A fifth water resides elsewhere
Water crisis in the Democratic Republic of the Congo Kivu. Furthermore, funding is heavily skewed towards the city of Kinshasa, receiving almost 40 percent of total investments in the urban water sector. The majority of the DRC's population without access to safe drinking water lives in rural areas. The rural water sector of the DRC has been neglected for many years and is characterized by a deteriorated infrastructure due to lack of maintenance and spare parts. Furthermore, many water systems are of poor construction quality. The major source of rural water supply are springs, accounting for approximately 90 percent of the total rural water supply. Springs have the advantage