Finding mass based on amu and % abundance

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SUMMARY

The average atomic mass of oxygen can be calculated using the isotopes' atomic mass units (amu) and their natural percent abundances. Oxygen-16 has an amu of 15.995 with a 99.759% abundance, Oxygen-17 has an amu of 16.995 with a 0.037% abundance, and Oxygen-18 has an amu of 17.999 with a 0.204% abundance. The formula for the average atomic mass is: AverageAMU = (0.99759 * 15.995) + (0.00037 * 16.995) + (0.00204 * 17.999), resulting in an average atomic mass of approximately 15.999 amu.

PREREQUISITES
  • Understanding of atomic mass units (amu)
  • Knowledge of isotopes and their percent abundance
  • Basic algebra skills for percentage calculations
  • Familiarity with the concept of weighted averages
NEXT STEPS
  • Study the concept of isotopic distribution in elements
  • Learn about the calculation of average atomic mass in chemistry
  • Explore the significance of percent abundance in isotopes
  • Review weighted average calculations in mathematical contexts
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Chemistry students, educators, and anyone interested in understanding isotopic calculations and average atomic mass determination.

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Homework Statement



Oxygen has 3 isotopes. Oxygen-16 has the amu of 15.995 and its natural percent abundance is 99.759. Oxygen-17 has a mass of 16.995 amu and its natural percent abundance is 0.037. Oxygen-18 has a mass of 17.999 amu and its natural percent abundance is 0.204. What is the average atomic mass of oxygen?

Homework Equations



I think I forgot these...

The Attempt at a Solution



I couldn't remember what the process is supposed to look like to figure this sort of problem out, so I tried to multiply the mass by the percent abundance, but the answers made very little sense. If somebody could help me figure out where I messed up, PLEASE RESPOND!
 
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The average atomic mass of an element is much like a simple mixture problem that you learn in first year Algebra such that you can resort directly to percentage contributions formula.

AverageAMU = 0.99759*16 + 0.00037*17 + 0.00204*18
 
Thank you so much!
 

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