Tetraboric acid

Summary

Tetraboric acid or pyroboric acid is a chemical compound with empirical formula H2B4O7.[2] It is a colourless water-soluble solid formed by the dehydration or polymerization boric acid.

Tetraboric acid
Names
IUPAC name
  • 3,7-Dihydroxy-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonane
  • Pyroboric acid
Identifiers
  • 12447-38-0
3D model (JSmol)
  • Interactive image
ChemSpider
  • 450911 checkY
  • 516845
  • InChI=1S/B4H2O7/c5-1-9-3(7)11-4(8)10-2-6/h7-8H checkY
    Key: RTANKYMJXZNJGQ-UHFFFAOYSA-N checkY
  • OB(OB=O)OB(O)OB=O
Properties
B4H2O7
Molar mass 157.25 g·mol−1
Appearance white solid
Melting point 236 °C (457 °F; 509 K)[1]
Conjugate base Tetraborate
Hazards
GHS labelling:
Warning
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Tetraboric acid is formally the parent acid of the tetraborate anion [B4O7]2−.

Preparation edit

Tetraboric acid can be obtained by heating orthoboric acid B(OH)3 above about 170 °C:[3][4]

4 B(OH)3H2B4O7 + 5 H2O

References edit

  1. ^ Abdullah Selim Parlakyigit and Celaletdin Ergun (2022): "Facile synthesis method for in situ composites of TiB2/B4C and ZrB2/B4C." Journal of the Australian Ceramic Society, volume 58, pages 411–420. doi:10.1007/s41779-021-00700-3
  2. ^ Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. ISBN 0-7506-3365-4.
  3. ^ Gurwinder Kaur, Shagun Kainth, Rohit Kumar, Piyush Sharma and O. P. Pandey (2021): "Reaction kinetics during non-isothermal solid-state synthesis of boron trioxide via boric acid dehydration." Reaction Kinetics, Mechanisms and Catalysis, volume 134, pages 347–359. doi:10.1007/s11144-021-02084-8
  4. ^ Siavash Aghili, Masoud Panjepour, and Mahmood Meratian (2018): "Kinetic analysis of formation of boron trioxide from thermal decomposition of boric acid under non-isothermal conditions." Journal of Thermal Analysis and Calorimetry, volume 131, pages 2443–2455. doi:10.1007/s10973-017-6740-3