AP Chemistry· difficulty 2/5
The mass spectrum of a pure element shows three peaks at m/z = 24, 25, and 26 with relative abundances 78.99%, 10.00%, and 11.01%.
What is the average atomic mass of this element?
26.00 amu
24.00 amu
24.32 amu
25.00 amu
Explanation
(24)(0.7899) + (25)(0.1000) + (26)(0.1101) = 24.32 amu, matching magnesium.
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