Potassium dichromate - physico-chemical properties and application

Potassium dichromate is non-traceablecrystals are predominantly orange (sometimes reddish), which dissolve well in the aqueous medium and resemble the finest needles or plates in shape. When interacting with a substance, the aqueous solution acquires an acidic reaction.

Potassium dichromate is a highly toxic, carcinogenic substance and the strongest oxidant. Spray solutions can destroy the skin, cartilage tissue, and inhalation of vapors - 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 K₂Cr₂O₇:

2KCl + Na₂Cr₂O₇ → K₂Cr₂O₇ + 2NaCl.

This substance is used in industry. Technical potassium dichromate is used for the production of matches, dry batteries, inorganic pigments, paint coatings, as well as in organic synthesis - for obtaining various kinds of chemical compounds.

Red-yellow solution of potassium dichromatestains litmus paper in pale red color. With further boiling, the chemical solution acquires a characteristic dark red color. When the temperature reaches 398 ^oC potassium dichromate begins to melt and turns into a liquid of a dark brown color, which upon subsequent cooling solidifies and crystallizes. Above 500 ^oC substance completely decomposes to the formation of oxygen, chromium oxide and potassium chromate.

Physicochemical properties of potassium dichromate

Index	unit of measurement	Value
crystal cell		triclinic or monoclinic
refraction		1,738
molecular weight		294,19
specific gravity	g / cm3	2,684
boiling temperature	oC	398
melting temperature	oC	completely decomposes at 500
solubility in 100 grams of water at a temperature of:	g
0 oC		4,7
20oC		11,1
100oC		102

Rules for storage and transportation of a chemical substance of an increased hazard class

Technical potassium dichromate can be transportedany kind of covered transport, except air. A chemical substance, packed in special containers intended for one-time use, can be transported by open rolling stock. Technical potassium dichromate must be stored in dry warehouses, while the product in specialized containers of one-time use can be stored in open areas equipped with a hard surface for water drainage.

Packing of a chemical belonging to the first class of danger

Technical potassium dichromate is packed inspecially designed steel drums, as well as polyethylene bags, consisting of five layers, weighing up to 50 kg. It is allowed to pack in soft containers of specialized purpose for one-time use.

The established hazard class for the chemical

Technical potassium dichromate is explosive and fire-hazardous. By the degree of impact on the human body, he was given the first class of danger. When working with a chemical, it is necessary to observe safety precautions, to be extremely cautious and attentive, and personal protective equipment for the skin and respiratory organs should be used.

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