Carbon dioxide

Carbon dioxide (dioxide of carbon, CO2) - coal acid anhydride. Gas is colorless and odorless, heavier than air 1,509 times. Under the pressure of carbonic gas becomes a liquid; liquefied CO2 stored in steel tanks. Steaming, liquid carbon dioxide is converted into snow-white mass which is pressed and used as coolant called "dry ice".
Carbon dioxide does not burn or support combustion, therefore it is used for fighting fires (fire extinguishers). In 1 l of water at temperature of 20 degrees and a pressure of 1 atmosphere dissolves 0,88 l of carbon dioxide. A small part of dissolved carbon dioxide reacts with water to form unstable carbonic acid (see). With increasing pressure solubility CO2 increases; this property carbon dioxide is used in the manufacture of carbonated drinks (in particular, the mineral water). The atmosphere contains about 0,03 about. % carbon dioxide, in the air exhaled by person - to 4%. In a large concentration of carbon dioxide is toxic. Stay in the air containing about 10% of carbon dioxide (in mines, caves, cellars), causes dizziness, noise in the ears, headache. In the future, somnolence, breathing slows cardiac activity weakened. Inhalation of high concentrations of carbon dioxide possible death from respiratory arrest (at 20% - within a few seconds). Cardiac activity continues for some time after you stop breathing.
First aid : remove victim to fresh air, artificial respiration, oxygen, heart funds.
Carbon dioxide plays a crucial role in the life and the carbon cycle (see) in nature. Along with bicarbonate carbon dioxide forms a crucial buffer system of blood; through the chemoreceptor carotid sinus affecting the medulla, CO2 participates in the regulation of respiration (see) and circulation (see). A mixture of 95% oxygen and 5% carbon dioxide (Carbogen) is used to assist with asphyxia, drug poisoning, carbon monoxide, etc.