Calcium selenide
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| __ Ca 2+ __ Se 2− | |||||||||||||||||||
| Crystal system | |||||||||||||||||||
| Space group |
Fm 3 m (No. 225) |
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| General | |||||||||||||||||||
| Surname | Calcium selenide | ||||||||||||||||||
| Ratio formula | CaSe | ||||||||||||||||||
| Brief description |
white-brown powder |
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| properties | |||||||||||||||||||
| Molar mass | 119.038 g mol −1 | ||||||||||||||||||
| Physical state |
firmly |
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| density |
3.57 g cm −3 (20 ° C) |
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| Melting point |
1408 ° C |
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| solubility |
decomposes in water |
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| safety instructions | |||||||||||||||||||
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | |||||||||||||||||||
Calcium selenide , CaSe, is the calcium salt of hydrogen selenium .
Extraction and presentation
The reduction of calcium selenate with hydrogen creates not only water but also the salt.
The direct reaction of both elements also results in calcium selenide. This is done under an inert atmosphere and at 550 ° C, but the yield is only 50%.
properties
Physical Properties
Calcium selenide has a cubic structure analogous to the other alkaline earth chalcogenides . It has room group Fm 3 m (room group no. 225) .
Chemical properties
The compound decomposes on contact with oxygen at the melting point to calcium oxide and selenium dioxide . Calcium selenide decomposes in water at room temperature .
use
The most common use of calcium selenide is as a phosphor . It glows in blue color and can be excited by infrared radiation .
toxicology
Calcium selenide is toxic when ingested or inhaled . With repeated or long exposure it damages the organs.