METHODS FOR THE DETERMINATION OF THE CARBON-DIOXIDE EVOLVED FROM EFFERVESCENT SYSTEMS

Different methods for determining the carbon dioxide evolved from effe rvescent systems are described. In addition, a comparison between some of them is carried out when a stoechiometric mixture of L-tartaric ac id and sodium bicarbonate reacts. The methods compared are: gravimetri c, volumetric and gasometric. The gravimetric methods can be direct or indirect. The direct ones are based on taking in the carbon dioxide b y a sorbent substance. The increase of weight after the absorption rep resents the CO2 evolved. In the indirect gravimetric methods the amoun t of carbon dioxide is determined by substraction of the weight of the sample after and before the effervescent reaction. The volumetric met hods are based on an acid-base titration. In the method used, the carb on dioxide released reacts with barium hydroxide. The excess of barium hydroxide is titrated with oxalic acid. It is possible to calculate t hen the carbon dioxide produced in the reaction from the volume of oxa lic acid used.In the gasometric methods the volume of gas is directly determined by the displacement of a solution when the gas is released. The gasometric method seems to be the most efficient among the studie d ones.