Potassium selenate

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Potassium selenate
Identifiers
3D model (JSmol)
ECHA InfoCard 100.029.286
EC Number
  • 232-214-7
RTECS number
  • VS6600000
Properties
K
2
SeO
4
Molar mass 221.2 g/mol[1]
Appearance colorless crystals
hygroscopic
Odor odorless
Density 3.07 g/cm3[2]
1.07 g/ml (0 °C)
1.11 g/ml (20 °C)
1.22 g/ml (100 °C)
1.539
Structure
orthorhombic
Hazards
NFPA 704 (fire diamond)
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilHealth code 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
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
2
SeO
4
, is an odorless, white solid that forms as the potassium salt of selenic acid. It is used in photography.

Preparation[edit]

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[edit]

  1. ^ "Potassium Selenate K2SeO4 Molecular Weight". EndMemo. Retrieved 2019-09-03.
  2. ^ "Potassium Selenate". American Elements. Retrieved 2019-09-03.
  3. ^ Rosenfeld, Irene; Beath, Orville A. (2013). Selenium: Geobotany, Biochemistry, Toxicity, and Nutrition. Elsevier Science. p. 305. ISBN 978-1-4832-7590-1.