Magnesium oxide (MgO), with the chemical formula MgO, is an inorganic compound that appears as a white, loose powder. It is an ionic compound with a high melting point (2800°C) and high boiling point (3600°C). It is insoluble in water at room temperature, with a water solubility of 6.2 mg/L (20°C). Magnesium oxide has a moderate density of 3.58 g/cm³ (25°C) and a molecular weight of 40.30. The product is typically classified into light magnesium oxide and heavy magnesium oxide, which have different properties and uses depending on the processing method and application field.