CHROMIC ACID DOMESTIC PRODUCT
CAS number: 7738-94-5
EC Number: 231-801-5
Gmelin Reference: 25982
Molecular formula: H2CrO4
Molar mass: 118.01 g mol-1
Appearance: Red crystals
Density: 1.201 g cm-3
Melting point: 197 ° C, 470 K, 387 ° C
Boiling point: 250 ° C, 523 K, 482 ° C (decomposed)
Its chemical formula is H2CrO4. The anhydride of chromic acid is chromium trioxide (CrO3). It is an unstable compound which reacts by itself to become di (bi) chromate acid (H2Cr2O7). It absorbs moisture from air. It dissolves very well in water and organic solvents such as acetic acid, pyridine and ether. The crude CrO3 is precipitated by precipitation from saturated sulfate acid and saturated sodium bichromate mixture. The precipitate is purified by crystallization or melting. It is an inorganic and strong acid and is also an oxidation agent.
Production and Reactions
Genuine chromic acid is only obtained by dissolving chromium trioxide (CrO3) in water. The washing solution may be prepared to remove residues remaining in glassware which are difficult to dissolve. For this solution, 5 g of Na2Cr2O7 or K2Cr2O7 (Merck 1.04952) are dissolved in 5 mL of distilled water, and 100 mL of concentrated sulfuric acid are added slowly. .
It is used in the production of chromium, which is the salt of chromic acid in chemical industry. It is also used as cleaning material in chemical laboratories.
In this sector, widely used in chrome plating. There is also a field of use for metal cleaning.
In the paint sector, it is used as an additive in the production of paints and as a rubber pigment.
This chemical is also; As a caustic in medicine, it is used in the production of glaze in the ceramics industry, in engraving processes, in the coloration of the glass sector.