How to Calculate the Average Mass of an Element from Its Mass Spectrum - Part 1

The mass spectrum of a sample containing a single element can be used to determine the identity of the isotopes of that element and the relative abundance of each isotope in nature.


The height of each line on a mass spectrum represents the relative amount of each mass.

The average atomic mass of an element can be estimated from the weighted average of the isotopic masses using the mass of each isotope and its relative abundance.

Question:

A portion of a mass spectrum of Ne is presented below. Estimate the average mass of naturally occurring atoms of Ne.



Click/tap to enlarge the image

Solution:



Click/tap to enlarge the image

A = Mass number of the isotope of an element

Elated to see elemental mass spectrum❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

References:

‌(1)    Jespersen, N. D.; Barron's Educational Series, Inc. Barron’s AP Chemistry; Barron’s Educational Series: Hauppauge, N.Y., 2012.

‌(2)    Brown, C.; Ford, M. Higher Level Chemistry, 2nd ed.; Pearson Education: Harlow, Essex, 2014.

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