A student was given a stock aluminum(III) solution with a concentration of 5.000 parts per million (ppm). (ppm are defined as mg/L for dilute aqueous solutions.) The student prepared five 100 mL standard solutions and an unknown as described in the procedure section of the experiment. The absorbance of each solution was read at 565 nm, using the blank to set zero absorbance. The results are tabulated below. Solution Volume of Al(III) stock solution used (mL) Absorbance 1 8.00 0.701 2 6.00 0.548 3 4.00 0.378 4 2.00 0.208 5 1.00 0.123 Unknown --- 0.534 3. What is your best estimate of the Al(III) concentration of the unknown sample in the cuvet based upon where its absorbance falls on the standard curve?

A student was given a stock aluminum(III) solution with a concentration of 5.000 parts per million (ppm). (ppm are defined as mg/L for dilute aqueous solutions.) The student prepared five 100 mL standard solutions and an unknown as described in the procedure section of the experiment. The absorbance of each solution was read at 565 nm, using the blank to set zero absorbance. The results are tabulated below. Solution Volume of Al(III) stock solution used (mL) Absorbance 1 8.00 0.701 2 6.00 0.548 3 4.00 0.378 4 2.00 0.208 5 1.00 0.123 Unknown --- 0.534 3. What is your best estimate of the Al(III) concentration of the unknown sample in the cuvet based upon where its absorbance falls on the standard curve?

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter13: The Chemistry Of Solutes And Solutions

Section: Chapter Questions

Problem 42QRT

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