Sodium sulfate anhydrous(na2so4) called Glauber Salt or sulfate of soda. It is chemically very stable and has an appearance of white crystalline solid. It has unsteady reaction towards most reducing or oxidizing agents at normal temperatures.
A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used.