Magnesium sulfate is a chemical compound containing magnesium and sulfate , with the formula MgSO 4 . In its hydrated form the pH is 6.0 (5.5 to 7.0). It is often encountered as the heptahydrate, MgSO 4 ·7H 2 O, commonly called Epsom salt . more

Magnesium sulfate is a chemical compound containing magnesium and sulfate , with the formula MgSO 4 . In its hydrated form the pH is 6.0 (5.5 to 7.0). It is often encountered as the heptahydrate, MgSO 4 ·7H 2 O, commonly called Epsom salt . Anhydrous magnesium sulfate is used as a drying agent. Since the anhydrous form is hygroscopic (readily absorbs water from the air) and therefore harder to weigh accurately, the hydrate is often preferred when preparing solutions, for example in medical preparations. Epsom salt has been traditionally used as a component of bath salts . less