Calcium dihydrogen phosphate
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| General | ||||||||||||||||
| Surname | Calcium dihydrogen phosphate | |||||||||||||||
| other names |
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| Molecular formula | Ca (H 2 PO 4 ) 2 | |||||||||||||||
| Brief description |
white, odorless solid |
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| properties | ||||||||||||||||
| Molar mass | 234.06 g mol −1 | |||||||||||||||
| Physical state |
firmly |
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| density |
2.22 g cm −3 |
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| Melting point |
at 100 ° C water release of the monohydrate |
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| boiling point |
200 ° C (decomposition) |
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| solubility |
18 g l −1 in water |
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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 dihydrogen phosphate is a calcium salt of orthophosphoric acid , belongs to the phosphates and has the composition Ca (H 2 PO 4 ) 2 . It is a colorless powder that is moderately soluble in water. The use of common names such as calcium biphosphate , monocalcium phosphate or monocalcium orthophosphate is misleading.
use
Calcium dihydrogen phosphate is a major component in phosphate fertilizers. It is also contained in many baking powders and feed additives as an acidity regulator or separating agent . Calcium dihydrogen phosphate, together with calcium hydrogen phosphate and calcium phosphate, is approved in the EU as a food additive under the common number E 341 ("calcium phosphate") for certain foods with different maximum quantity restrictions, also for organic foods . According to the Additive Admissions Ordinance , these are - largely uniform for most of the approved phosphates - individual specifications for a wide range of numerous different types of food. The maximum permitted amounts vary from 0.5 to 50 grams per kilogram (in creamer for vending machines) or the lack of a fixed limit ( quantum satis - as required, for food supplements and sometimes for chewing gum). Phosphorus is suspected of causing hyperactivity , allergic reactions and osteoporosis . A permissible daily dose of 70 milligrams per kilogram of body weight was set for the total amount of phosphoric acid and phosphates ingested.