Sodium tungstate dihydrate
SIGMA/72069 - BioUltra, ≥99.0% (T)
Synonym: Tungstic acid sodium salt dihydrate
CAS Number: 10213-10-2
Empirical Formula (Hill Notation): Na2O4W · 2H2O
Molecular Weight: 329.85
EC Number: 236-743-4
MDL Number: MFCD00149190
Linear Formula: Na2WO4 · 2H2O
Product Type: Chemical
| λ | 1 M in H2O |
| anion traces | chloride (Cl-): ≤50 mg/kg |
| sulfate (SO42-): ≤100 mg/kg | |
| assay | ≥99.0% (T) |
| cation traces | As: ≤0.5 mg/kg |
| Ca: ≤10 mg/kg | |
| Cd: ≤5 mg/kg | |
| Co: ≤5 mg/kg | |
| Cr: ≤5 mg/kg | |
| Cu: ≤5 mg/kg | |
| Fe: ≤5 mg/kg | |
| K: ≤50 mg/kg | |
| Mg: ≤5 mg/kg | |
| Mn: ≤5 mg/kg | |
| Ni: ≤5 mg/kg | |
| Pb: ≤10 mg/kg | |
| Zn: ≤5 mg/kg | |
| form | crystals |
| grade | reagent grade |
| impurities | insoluble matter, passes filter test |
| ≤0.001% total nitrogen (N) | |
| ≤0.1% free alkali (as NaOH) | |
| InChI | 1S/2Na.2H2O.4O.W/h;;2*1H2 |
| InChI key | WPZFLQRLSGVIAA-UHFFFAOYSA |
| mp | 698 °C (lit.) |
| pH | 9.5-11.5 (25 °C, 1 M in H2O) |
| product line | BioUltra |
| Quality Level | 100 ![]() |
| SMILES string | O.O.[Na+].[Na+].[O-][W]([ |
| solubility | H2O: 1 M at 20 °C, clear, colorless |
| UV absorption | λ: 260 nm Amax: ≤0.120 |
| λ: 280 nm Amax: ≤0.035 |
| Application: | Sodium tungstate dihydrate has been used in bioluminescence assays and to synthesize polycrystalline samples. |
| General description: | Sodium tungstate dihydrate is a sodium salt of tungstic acid, which occurs as white colorless crystals. |
| Other Notes: | Stain in electron microscopy (nucleic acids, certain glycoproteins); Protein precipitant. |
| Symbol | GHS07 |
| Signal word | Warning |
| Hazard statements | H302 |
| Hazard Codes | Xn |
| Risk Statements | 22 |
| Safety Statements | 36 |
| RIDADR | NONH for all modes of transport |
| WGK Germany | WGK 1 |
| Flash Point(F) | Not applicable |
| Flash Point(C) | Not applicable |
| Purity | ≥99.0% (T) |
| mp | 698 °C (lit.) |
| UNSPSC | 12352302 |


