Difference between revisions of "Boron trioxide"

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(Preparation)
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==Preparation==
 
==Preparation==
Boric acid can be dehydrated above 300 degrees to form boron trioxide. Boron trioxide does not reabsorb this water from the atmosphere so is stable at room temperature.  
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Boric acid can be dehydrated above 300 degrees to form boron trioxide. Boron trioxide prepared at up to 800 degrees is a desiccant but it is slow acting if not finely powdered.  Made at higher temperature it has an induction period.
  
 
==Projects==
 
==Projects==

Revision as of 20:14, 9 December 2016

Boron trioxide
B2O3.JPG
Names
IUPAC name
Boron trioxide
Properties
B2O3
Appearance Hard glassy solid or white powder.
Density 2.460 g/cm3, liquid;

2.55 g/cm3, trigonal;
3.11–3.146 g/cm3, monoclinic

Melting point 450 °C (842 °F; 723 K)
Boiling point 1,860 °C (3,380 °F; 2,130 K)
Solubility methanol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Boron trioxide is a glass like solid or white powder with the chemical formula B2O3.

Properties

Chemical

Boron trioxide is very unreactive. It can however be reduced to elemental boron with magnesium or aluminum powder in a thermite reaction.

Physical

When produced from boric acid, it forms as a non crystaline mass that is very hard and difficuilt to grind, forming a very fine powder when ground very similar to a solid plane of glass.

Availability

It is used in glassmaking, whether as a boron additive for making borosilicate glass or as a fluxing agent so this may be a source, however it is easy to produce from the starting materials boric acid or borax.

Preparation

Boric acid can be dehydrated above 300 degrees to form boron trioxide. Boron trioxide prepared at up to 800 degrees is a desiccant but it is slow acting if not finely powdered. Made at higher temperature it has an induction period.

Projects

Handling

Safety

Storage

No special storage is required, storing it in closed bottles is fairly enough.

Disposal

References

Relevant Sciencemadness threads