Potassium dichromate is a non-tracking crystals of predominantly orange color (sometimes reddish), which dissolve well in an aqueous medium and resemble the finest needles or plates in shape. When interacting with a substance, an aqueous solution acquires an acid reaction.
Potassium dichromate is a highly toxic, carcinogenic substance and a powerful oxidizing agent. Spray solution can destroy the skin, cartilage, and inhalation of fumes - the respiratory tract.
At a temperature of about 1300 ° C, as a result of the exchange reaction of sodium dichromate and potassium chloride, potassium dichromate is obtained, the formula of which is K 2 Cr 2 O 7 :
2KCl + Na 2 Cr 2 O 7 → K 2 Cr 2 O 7 + 2NaCl.
This substance is used in industry. Technical potassium dichromate is used for the production of matches, dry batteries, inorganic pigments, paints and varnishes, as well as in organic synthesis for the production of various kinds of chemical compounds.
The red-yellow solution of potassium dichromate stains the litmus test with a pale red color. With further boiling, the chemical solution acquires a characteristic dark red hue. When the temperature reaches 398 o C, the potassium dichromate begins to melt and turns into a dark brown liquid, which, upon subsequent cooling, hardens and crystallizes. Above 500 ° C., the substance decomposes completely to form oxygen, chromium oxide and potassium chromate.
Physico-chemical properties of potassium dichromate
| Index | unit of measurement | Value |
| crystal cell | | triclinic or monoclinic |
| refraction | | 1,738 |
| molecular weight | | 294.19 |
| specific gravity | g / cm 3 | 2,684 |
| boiling temperature | o C | 398 |
| melting temperature | o C | completely decomposes at 500 |
| solubility in 100 grams of water at temperature: | g | |
| 0 o C | | 4.7 |
| 20 o C | | 11.1 |
| 100 o C | | 102 |
Rules for storing and transporting hazardous chemicals
Technical potassium dichromate can be transported by any means of covered transport, with the exception of air transport. A chemical packaged in special containers intended for single use can be transported by open rolling stock. Technical potassium dichromate must be stored in dry warehouses, while the product in specialized disposable containers can be stored in open areas equipped with a hard coating for water flow.
Packaging of a chemical of the first hazard class
Technical potassium dichromate is packaged in specially designed steel drums, as well as plastic bags consisting of five layers, weighing up to 50 kg. Allowed packing in soft containers for specialized purposes for single use.
Chemical hazard class established
Technical potassium bichromate is explosive and fire hazard. According to the degree of impact on the human body, it is assigned the first hazard class. When working with a chemical substance, it is necessary to observe safety precautions, be extremely careful and attentive, and personal protective equipment for the skin and respiratory organs should also be used.