Calculations (Show all work!)
1.) Inspect your data carefully and classify the isotopes as shown below:
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Isotope A (less than 1.00 g)!
Isotope B (1.00 - 1.10 g)! !
Isotope C (1.11 - 1.20 g)! !
Isotope D (1.21 - 1.30 g)
Isotope E (1.31 g or greater)
How many different isotopes do you have? !
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2.) Calculate the percent abundance for each isotope found in your sample (hint: x/20 for each).
3.) Calculate the average (mean) mass for each isotope.
4.) Using the fractional abundance and the average (mean) mass for each isotope, calculate the
atomic mass of Td. (Box your answer.)
Questions
1.) Was the mass of 20 beans equal to the mass of 20 times one bean? Explain why or why not.
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2.) If tigardium was an actual element, what would account for the fact that its atoms had different
masses?
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3.) How are the isotopes of an element similar?!!
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How are the isotopes of an element different? ! !
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4.) Copper has two isotopes, copper-63 and copper-65. Calculate the atomic mass for copper
given the following data below. Show your work!
Isotope
Percent abundance
Mass
copper-63
69.1%
62.930 amu
copper-65
30.9%
64.928 amu