Detn of Acidity

In Ref 2 is described analysis of industrial EtAcet liable to contain water, ethanol and ethyl formate with traces of acidity, whereas in Ref 3 is described a precise method for detn of acidity in EtAcet... 

For detn of acidity in colorless, non-fuming sulfuric acid, an aq soln of a weighed sample is titrated with std NaOH in the presence of an indicator, such as methyl red... 

For quantitative detn of acidity two methods can be used a) If the sample melts below 100°(such as TNT, DNT, etc) shake it with boiling neutral w, cool, filter the extract and titrate it with std alkali (such as 0.05N NaOH) in presence of an indicator or det the pH of the extract b)If the sample melts above 100° (such as RDX) or does not melt at all (such as NQ, dissolve it in neutral acet, add neutral w to reppt the sample, filter the slurry and det the acidity of filtrate either by titration with std alkali or by the pH method... 

Coefficient d echange (Fr) (Exchange Coefficient). In order to det if a NC is sufficiently stabilized, Vieille detd titrimetrically the amt of acid (expressed as mg of H2S04) removed from each lOOg of NC in each hour of washing with w or dil alkali solns. He found that as soon as the coeficient drops to ca 5 (from original of about 150), the stabilization may be considered as completed. This method was improved by using pH meters for detn of acidity... 

Detn of acidity and alkalinity. Percentage of nitrogen by nitrometer. Stability test with.KI-... 

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