Explore AP Chemistry 1.2.A questions on using mass spectra to identify isotopes, interpret relative abundance, and estimate weighted average atomic mass.
Answer the following questions about magnesium.
An incomplete mass spectrum for magnesium is shown in the diagram.
The percent abundance of magnesium-24 is 79\%. The percent abundances of the other two natural isotopes of magnesium, magnesium-25 and magnesium-26, are approximately equal.
Complete the mass spectrum in part A by drawing thick lines in the appropriate locations to represent the percent abundance of magnesium-25 and magnesium-26.
A (i) For the correct plotted lines:
Point 01
The abundance for the two lines should be between 10 and 11.
Describe the difference in atomic structure that accounts for the difference in mass between magnesium-25 and magnesium-26.
(ii) For the correct answer:
Point 02
Magnesium-26 has one more neutron than magnesium-25 does.