Abstrait

Estimation of copper in copper salts at different pHconditions and buffer media by iodo-potentiometric technique

H.C.Anandamurthy, O.G.Palanna

Copper in cupric salt / brass is, generally, estimated by the well known iodometric method. Many modifications were made to the procedure to improve results. In the present investigation, for the first time, copper in copper solutions are estimated by using iodo-potentiometric technique of analysis. In the present paper, the results of both the redox potentiometric and titrimetric methods of analysis are correlated successfully to estimate the amount of copper in the samples of copper salts at different pH and buffer media conditions. The results of the present investigation clearly hints that copper can be estimated effectively at pH between 2.0 and 3.5 usingNaOH and CH3COOH; while the desired pH range, preferably, is 2.0 - 3.0 for ammonia and acetic acid as buffer reagents. The results obtained for copper salts using NaOH or NH4OH, with citric acid as acidifying agent, is poor. This is due to the formation of a product of complexation with one of the reagents. However, it can be observed that the estimation of copper gives fairly good result with error, if the pH of the solution is maintained at pH = 2.0 by the addition of citric acid. Thus, redox iodo- potentiometric technique is also used as an excellent analytical tool for analysis; and the results obtained for copper estimation are comparable to any standardmethods of analysis.