Given the relative abundance of the following naturally occurring isotopes of oxygen: O-16: 99.76%, O-17: 0.037%, and O-18: 0.204%, how would you calculate atomic mass?

1 Answer
Oct 26, 2015

#"AAM"=sum("isotope mass"xx"percent Abundance")#

Explanation:

The average atomic mass (#"AAM"#) is calculated by the following expression:

#"AAM"=sum ("isotope mass"xx"percent Abundance")#

Therefore, to calculate the average atomic mass of oxygen:

#"AAM"=(16xx0.9976)+(17xx0.00037)+(18xx0.00204)=16.00 " a.m.u."#