There are two isotopes of an unknown element, X-19 and X-21. The abundance of X-19 is 12.01%. a) A weighted average uses the percentages of each isotope to scale their contribution to the total mass. Each isotope's contribution is the percentage (in decimal form) multiplied by the mass of the isotope. What is the contribution (in amu) to the weighted average from the X-19 isotope, which has a mass of 19.00 amu? b) What is the percentage of the X-21 isotope? c) What is the contribution (in amu) to the weighted average from the X-21 isotope, which has a mass of 21.00 amu? d) What is the average atomic mass (in amu) of this element using four significant figures?

There are two isotopes of an unknown element, X-19 and X-21. The abundance of X-19 is 12.01%. a) A weighted average uses the percentages of each isotope to scale their contribution to the total mass. Each isotope's contribution is the percentage (in decimal form) multiplied by the mass of the isotope. What is the contribution (in amu) to the weighted average from the X-19 isotope, which has a mass of 19.00 amu? b) What is the percentage of the X-21 isotope? c) What is the contribution (in amu) to the weighted average from the X-21 isotope, which has a mass of 21.00 amu? d) What is the average atomic mass (in amu) of this element using four significant figures?

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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