laboratory by the action of dilute hydrochloric acid on metal carbonates. CaCO + 2HCl CaCl + H O + CO Properties It is a colourless, nonflammable gas and is heavier than air. Its critical temperature is 31⁰ C and can be readily liquefied. Carbon dioxide is a very stable compound.
Even at K only % decomposes to form carbon monoxide and oxygen. At still higher temperature it decomposes into carbon and oxygen. CO CO + ½O K CO C + O high temperature Oxidising behaviour: At elevated temperatures, it acts as a strong oxidising agent. For example, CO + 2Mg 2MgO + C Water gas equilibrium: The equilibrium involved in the reaction between carbon dioxide and hydrogen, has many industrial applications and is called water gas equilibrium.
CO + H CO + H O Acidic behaviour: The aqueous solution of carbon dioxide is slightly acidic as it forms carbonic acid. CO + H O H CO H + + HCO - Structure of carbon dioxide Carbon dioxide has a linear structure with equal bond distance for the both C-O bonds. In this molecule there is two C-O sigma bond. In addition there is 3c-4e bond covering all the three atoms.
C C C Figure . Structure of carbon dixide Uses of carbon dioxide . Carbon dioxide is used to produce an inert atomosphere for chemical processing. .
Biologically, it is important for photosynthesis. - - - - . It is also used as fire extinguisher and as a propellent gas. .
It is used in the production of carbonated beverages and in the production of foam. . . Silicon tetrachloride: Preparation: Silicon tetrachloride can be prepared by passing dry chlorine over an intimate mixture of silica and carbon by heating to K in a porcelain tube SiO + 2C + 2Cl SiCl + 2CO On commercial scale, reaction of silicon with hydrogen chloride gas occurs above K Si + 4HCl