Wikipedia
Sodium perchlorate
Sodium perchlorate is the inorganic compound with the chemical formula Na Cl O. It is the most soluble of the common perchlorate salts. It is a white crystalline, hygroscopic solid that is highly soluble in water and in alcohol. It usually comes as the monohydrate, which has a rhombic crystal system.
Its heat of formation is −382.75 kJ mol.