(c) In an experiment, a student determined the mass of iron in an unknown biological sample. From the experiment, the student found 49.90 mg of iron. UE (1) What type of balance do you think the student used? (ii) In general, what are the two common methods of measuring mass in the laboratory? and (ii) If the % experimental error was 0.20%, What was the actual mass of the iron in the sample? (Assume that the actual mass was larger than the mass determined by the student). Show your calculations. (d) Consider a 15.0-g sample of a potassium salt. This compound is 32.86% by mass of potassium. Calculate the number of potassium ions present in this sample.

(c) In an experiment, a student determined the mass of iron in an unknown biological sample. From the experiment, the student found 49.90 mg of iron. UE (1) What type of balance do you think the student used? (ii) In general, what are the two common methods of measuring mass in the laboratory? and (ii) If the % experimental error was 0.20%, What was the actual mass of the iron in the sample? (Assume that the actual mass was larger than the mass determined by the student). Show your calculations. (d) Consider a 15.0-g sample of a potassium salt. This compound is 32.86% by mass of potassium. Calculate the number of potassium ions present in this sample.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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