Potassium selenate

Potassium selenate

Identifiers
CAS Number	7790-59-2
3D model (Jmol)	Interactive image
ECHA InfoCard	100.029.286
EC Number	232-214-7
PubChem	62680
RTECS number	VS6600000
InChI InChI=1S/2K.H2O4Se/c;;1-5(2,3)4/h;;(H2,1,2,3,4)/q2*+1;/p-2 Key: YAZJAPBTUDGMKO-UHFFFAOYSA-L
SMILES [K+].[K+].[O-][Se]([O-])(=O)=O
Properties
Chemical formula	K 2SeO 4
Molar mass	221.2 g/mol[1]
Appearance	colorless crystals hygroscopic
Odor	odorless
Density	3.07 g/cm3[2]
Solubility in water	1.07 g/ml (0 °C) 1.11 g/ml (20 °C) 1.22 g/ml (100 °C)
Refractive index (nD)	1.539
Structure
Crystal structure	orthorhombic
Hazards
NFPA 704	1 3 0
Related compounds
Other anions	Potassium sulfate
Other cations	Sodium selenate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Potassium selenate, K
2SeO
4, is an odorless, white solid that forms as the potassium salt of selenic acid. It is used in photography.

Preparation

Potassium selenate is produced by the reaction of selenium trioxide and potassium hydroxide.

SeO₃ + 2 KOH → K₂SeO₄ + H₂O

Alternatively, it can be made by reacting selenous acid with potassium hydroxide, and then oxidizing the resulting potassium selenite with bromine.^[3]

H₂SeO₃ + 2 KOH → K₂SeO₃ + 2 H₂O

K₂SeO₃ + 2 KOH + Br₂ → K₂SeO₄ + 2 KBr + H₂O

References