Question

1- Spectrophotometric determination of copper. was this experiment quantitative?

2- Briefly, what is the purpose of the blank measurement (when the cuvette was filled with water)?

Answer 1

(1)
Copper is one of the several metals that play an important role in the biological systems. Copper occurs naturally in many vegetables, meat and grains. Increased copper levels in drinking water may also cause increase in lead levels which in turn may be associated with liver damage and kidney diseases [1]. Copper kills a variety of potentially harmful pathogens. On Feb 29, 2008 the United States EPA registered 275 alloys containing greater than 65 % nominal copper content as anti-microbial materials [2]. In view of the important role played by copper in biological and environmental areas, an attempt has been made to study copper through spectrophotometric determination by using piperazine as a reagent.

The experimental conditions for quantitative results have been developed by studying the effect of various parameters that follow.
1. Effect of ammonium acetate:
2.Effect of reagent concentration.

(2.)
The blank solution consists of the solvent used to dissolve the specimen. Because other compounds in a solution (or the solvent itself) may absorb the same wavelengths as the compound being analyzed, we compare the absorbance of the test solution to a reference blank. Ideally, the reference blank should contain everything found in the sample solution except the substance you are trying to analyze or measure.