Практикалық сабақтарының тақырыптары мен мазмұны Practical assignment №1
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- Бұл бет үшін навигация:
- Carbon Dioxide.
| Elementary Carbon. Carbon occurs in nature in its elementary state in two allotropic forms namely diamond, this being the hardest substance known, and graphite, a soft, black crystalline substance used as a lubricant. Having investigated all the substances thoroughly the scientists found charcoal, coke, and carbon black; to be microcrystalline or amorphous (noncrystalline) forms of carbon.
Carbon burns to form gases: carbon monoxide CO, and carbon dioxide CO2, the former being produced when there is a deficiency of oxygen or the flame temperature is very high. This investigation followed by others resulted in new discoveries in the field of carbon. It has been found out that carbon monoxide is a colourless, odourless gas with small solubility in water. It is poisonous, because of its ability to combine with the hemoglobin in the blood in the same way that oxygen does, and thus to prevent the hemolobin from combining with oxygen in the lungs and carrying it to the tissues. It should be noted that the exhaust as from automobile engines contains some carbon. Nevertheless carbon monoxide is a valuable industrial gas, for use as a fuel and as a reducing agent. Carbon Dioxide. Carbon dioxide is a colourless, odourless gas with a weakly acid taste, due to the formation of some carbonic acid when it is dissolved in water. It appears to be about 50'/o heavier than air. It is easily soluble in water, one liter of water at O'C dissolving 1,713 ml of the gas under 1 atm pressure. When crystalline carbon dioxide is heated from a very low temperature its vapour pressure reaches 1 atm at 79' at which temperature it vaporizes without melting. If pressure were increased to 2.5 atm the crystalline substance would melt to a liquid at 56.6'. Under ordinary pressure, then, the solid substance could be changed directly to a gas. Carbon dioxide is known to combine with water to form carbonic acid H2CO3, it being a weak acid. If you studied all the properties more thoroughly you would see that carbon dioxide is used for the manufacture of sodium carbonate, sodium hydrogen carbonate, and carbonated water and for many other uses. From this short review it's clear that chemistry of carbon and its compounds is a very important field of chemistry and should be studied carefully. жүктеу/скачать 64,23 Kb. Достарыңызбен бөлісу:
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