Sodium nitrate, with a melting point of 306.8 ℃ and a density of 2.257 g/cm3 (at 20 ℃), is colorless transparent or white slightly yellow rhombic crystal. It tastes bitter and salty, is easily soluble in water and liquid ammonia, is slightly soluble in glycerin and ethanol, and is easy to deliquescence. Especially when it contains a small amount of sodium chloride impurities, the deliquescence of sodium nitrate is greatly increased. When it is dissolved in water, the solution temperature decreases and the solution is neutral. When heated, sodium nitrate is easily decomposed into and. Sodium nitrate can support combustion and must be stored in a cool and ventilated place.