A is a radioactive substance with a half-life of 2 hours. B is a radioactive substance with a half-life of 1 hours. Substance B initially has twice as many atoms of substance A. Which of the following statements about samples A and B is true? A. After 1 hour, a larger percentage of undecayed atoms will be left in sample B than in sample A. B. After 1 hour, a larger number of atoms will have decayed in sample A than in sample B. C. After 2 hours, both samples will have the same number of undecayed atoms. D. After 2 hours, the same number of atoms will have decayed in both samples.

A is a radioactive substance with a half-life of 2 hours. B is a radioactive substance with a half-life of 1 hours. Substance B initially has twice as many atoms of substance A. Which of the following statements about samples A and B is true? A. After 1 hour, a larger percentage of undecayed atoms will be left in sample B than in sample A. B. After 1 hour, a larger number of atoms will have decayed in sample A than in sample B. C. After 2 hours, both samples will have the same number of undecayed atoms. D. After 2 hours, the same number of atoms will have decayed in both samples.

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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