COMBUSTION METHOD

The percentage of carbon and hydrogen is determined by burning the organic compound in excess of oxygen and in presence of CuO. Carbon is oxidised to CO2 and hydrogen to water.

Mass of water is determined by passing it over anhydrous calcium chloride and that of carbon dioxide by passing over conc. Solution of KOH. Increase in their respective masses gives the amount of water and CO2 and from which, we calculate percentage of carbon and hydrogen.

Let the mass of the org. Compound is ‘m’ g and mass of water and carbon dioxide be ‘m1’ and ‘m2’ g respectively;

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