Average Atomic Mass.

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Presentation transcript:

Average Atomic Mass

AAM Weighted average of all the known isotopes of an element In order to find the AAM you need the % and mass for each isotope

Find the average atomic mass of the following element: 234U (0.01%), 235U(0.71%), 238U(99.28%)

In a sample of silicon, 92. 21% of the atoms have a mass of 27 In a sample of silicon, 92.21% of the atoms have a mass of 27.98 amu, 4.70% have a mass of 28.98 amu and 3.09% have a mass of 29.97 amu. What is the average atomic mass of the sample?

What is the average atomic mass of a sample of lead with the following composition?