An element has three naturally occurring isotopes. Use the information below to calculate the weighted average atomic mass of the element, showing both the setup and the final answer for the calculation.
isotope atomic mass percent abundance
x 1.01u 99,984%
y 2.01u 0.014%
z 3.02u 0.002%

Question

An element has three naturally occurring isotopes. Use the information below to calculate the weighted average atomic mass of the element, showing both the setup and the final answer for the calculation.
isotope      atomic mass    percent abundance
x                   1.01u           99,984%
y                    2.01u           0.014%
z                    3.02u           0.002%

cuanchi · Answer

you have to add the atomic mass of each isotope multiplied by the abundance divided by 100

(atomic mass "x" x 99.984/100) + (atomic mass "y" x 0.014/100) + (atomic mass "z" x 0.002/100) = average atomic mass