The method of standard additions was used to determine nitrite in a soil sample. A 1.00-mL portion of the sample was mixed with 22.00 mL of a colorimetric reagent, and the nitrite was converted to a colored product that produced a blank-corrected absorbance of 0.350. To 54.00 mL of the original sample, 1.00 mL of a standard solution of 1.00 × 10-³ M nitrite was added. The same color-forming procedure was followed, and the new absorbance was 0.560. What was the concentration of nitrite in the original undiluted sample? -3 Concentration = M

The method of standard additions was used to determine nitrite in a soil sample. A 1.00-mL portion of the sample was mixed with 22.00 mL of a colorimetric reagent, and the nitrite was converted to a colored product that produced a blank-corrected absorbance of 0.350. To 54.00 mL of the original sample, 1.00 mL of a standard solution of 1.00 × 10-³ M nitrite was added. The same color-forming procedure was followed, and the new absorbance was 0.560. What was the concentration of nitrite in the original undiluted sample? -3 Concentration = M

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter4: Reactions In Aqueous Solution

Section: Chapter Questions

Problem 77QAP: A 300.0-g sample of a solid is made up of a uniform mixture of NaNO3, MgCl2, and BaCl2. A 100.0-g...

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A 300.0-g sample of a solid is made up of a uniform mixture of NaNO3, MgCl2, and BaCl2. A 100.0-g sample of the mixture is dissolved in water and treated with an excess of KOH. The precipitate from the reaction has a mass of 13.47 g. The remaining 200.0-g sample is also dissolved in water and treated with an aqueous solution of AgNO3. The resulting precipitate has a mass of 195.8 g. What are the masses of NaNO3, MgCl2, and BaCl2 in the 300.0-g sample?
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