Atomic Mass Calculation Conclusion

What is the average atomic mass?

• The sum of the masses of its isotopes, each multiplied by its natural abundance

• The total number of protons in an element

• The total number of neutrons in an element

• The weight of an electron

Calculate the average atomic mass of an element with two isotopes. Isotope A has a mass of 10 amu and a relative abundance of 30%. Isotope B has a mass of 12 amu and a relative abundance of 70%.

• 13.4 amu

• 11.4 amu

• 12.6 amu

• 10.6 amu

Calculate the average atomic mass of an element with three isotopes. Isotope A has a mass of 10 amu and a relative abundance of 20%. Isotope B has a mass of 12 amu and a relative abundance of 50%. Isotope C has a mass of 14 amu and a relative abundance of 30%.

• 12.2 amu

• 11.5 amu

• 13.8 amu

• 15.6 amu

Calculate the average atomic mass of an element with three isotopes. Isotope A has a mass of 5 amu and a relative abundance of 10%. Isotope B has a mass of 6 amu and a relative abundance of 40%. Isotope C has a mass of 7 amu and a relative abundance of 50%.

Calculate the average atomic mass of element X when 34% of element X exists as X-272 and the remainder exists as X-274.

• 185.64amu
• 273.32amu
• 272.68amu
• 27.33amu

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

The average atomic mass of carbon is 12.01 amu. Carbon has two naturally occurring isotopes: Carbon-12 (mass = 12.00 amu, abundance = 98.90%) and Carbon-X (mass = unknown, abundance = 1.10%) The average atomic mass of carbon is 12.01 amu. What is the mass of Carbon-X?

he average atomic mass of uranium is 238.03 amu. Uranium has three naturally occurring isotopes: Uranium-238 (mass = 238.03 amu, abundance = 99.27%), Uranium-235 (mass = 235.04 amu, abundance = 0.72%), and Uranium-X (mass = unknown, abundance = 0.01%). What is the mass of Uranium-X?