Radioactive cobalt-56 decays with a half-life of 77.2 days. a. What is the value of k in s12 k = b. A sample contains 19.0 mg 56 Co. How many decay events will be produced in the first second? Assume the atomic mass of 56 Co is 55.9 u. decays/s c. A chemist obtains a fresh sample of 5° Co and measures its radioactivity. She then determines that to do an experiment, the radioactivity cannot fall below 25% of the initial measured value. How long does she have to do the experiment? days

Radioactive cobalt-56 decays with a half-life of 77.2 days. a. What is the value of k in s12 k = b. A sample contains 19.0 mg 56 Co. How many decay events will be produced in the first second? Assume the atomic mass of 56 Co is 55.9 u. decays/s c. A chemist obtains a fresh sample of 5° Co and measures its radioactivity. She then determines that to do an experiment, the radioactivity cannot fall below 25% of the initial measured value. How long does she have to do the experiment? days

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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