how to recaptulise sodium dichromate??
Answers
Answer:
Sodium dichromate is the inorganic compound with the formula Na2Cr2O7. Usually, however, the salt is handled as its dihydrate Na2Cr2O7·2H2O. Virtually all chromium ore is processed via conversion to sodium dichromate and virtually all compounds and materials based on chromium are prepared from this salt.In terms of reactivity and appearance, sodium dichromate and potassium dichromate are very similar. The sodium salt is, however, around twenty times more soluble in water than the potassium salt (49 g/L at 0 °C) and its equivalent weight is also lower, which is often desirable.
Sodium dichromate
Na2Cr2O7
Dichroman
Names
IUPAC name
Sodium dichromate
Other names
Chromic acid disodium salt
Identifiers
CAS Number
10588-01-9 ☑
7789-12-0 (dihydrate) ☒
3D model (JSmol)
SMILES
[Na+].[Na+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O
Properties
Chemical formula
Na2Cr2O7
Molar mass
261.97 g/mol (anhydrous)
298.00 g/mol (dihydrate)
Appearance
bright orange
Odor
odorless
Density
2.52 g/cm3
Melting point
356.7 °C (674.1 °F; 629.8 K)
Boiling point
400 °C (752 °F; 673 K) decomposes
Solubility in water
73 g/100 mL at 25 °C
Solubility in other solvents
soluble in methanol, ethanol
Refractive index (nD)
1.661 (dihydrate)
Hazards
Safety data sheet
ICSC 1369
EU classification (DSD) (outdated)
Oxidant (O)
Carc. Cat. 2
Muta. Cat. 2
Repr. Cat. 2
Very toxic (T+)
Harmful (Xn)
Corrosive (C)
Dangerous for the environment (N)
R-phrases (outdated)
R45, R46, R60, R61, R8, R21, R25, R26, R34, R42/43, R48/23, R50/53,
S-phrases (outdated)
S53, S45, S60, S61
NFPA 704 (fire diamond)
NFPA 704 four-colored diamond
041OX
Lethal dose or concentration (LD, LC):
LD50 (median dose)
50 mg/kg
Related compounds
Other anions
Sodium chromate
Sodium molybdate
Sodium tungstate
Other cations
Potassium dichromate
Ammonium dichromate