ANHYDROUSSODIUMTETRABORATE
- CAS No.
- Chemical Name:
- ANHYDROUSSODIUMTETRABORATE
- Synonyms
- ANHYDROUSSODIUMTETRABORATE
- CBNumber:
- CB51433011
- Molecular Formula:
- Molecular Weight:
- 0
- MDL Number:
- MOL File:
- Mol file
ANHYDROUSSODIUMTETRABORATE Chemical Properties,Uses,Production
Chemical Properties
Anhydrous sodium tetraborate is a large, colorless, transparent crystal, which effloresces superficially when stored in dry air. Water is split off on heating; above 350℃, Na3B4O7 is formed.
Preparation
To prepare very pure, formula-weight borax as a primary standard, good quality commercial product is recrystallized three times from water and dried to constant weight in a vacuum desiccator over a desiccant with suitable vapor pressure. Recent studies have shown that the best desiccant consists of solid NaCl, sucrose and a saturated sucrose solution. The correct water content (47.21%) is achieved by drying a sample in a Pt crucible, first on a steam bath, then at 200°C, and finally between 700-800°C. To check for any further impurities, cf. I. M. Kolthoff, Gravimetric Analysis, II (pp. 97-98).