Na2CO4.5H2O
White powder. Pentahydrate form. Also known as Soda Ash.

Safety

Warning
Causes serious eye irritation.
General: Read label before use. Keep out of reach of children. If medical advice is needed, have product container or label at hand.
Prevention: Wash hands thoroughly after handling. Wear eye protection.
Response: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. If eye irritation persists: Get medical advice.