Question

missed this? read section 4.8. calculating atomic mass: read section 4.8. you can click on the review link to access the section in your e text. part a an element has four naturally occurring isotopes; the table lists the mass and natural abundance of each isotope. find the atomic mass of the element. isotope mass (amu) natural abundance a 135.9072 0.2% b 137.9080 0.3% c 139.9054 88.4% d 141.9092 11.1% 140.1 amu 1.4×10⁴ amu 138.4 amu 139.1 amu submit request answer

Explanation:

Step1: Convert percentages to decimals

For isotope A: \(0.2\%=0.002\), for isotope B: \(0.3\% = 0.003\), for isotope C: \(88.4\%=0.884\), for isotope D: \(11.1\%=0.111\)

Step2: Calculate the contribution of each isotope

Contribution of A: \(135.9072\times0.002 = 0.2718144\)
Contribution of B: \(137.9080\times0.003=0.413724\)
Contribution of C: \(139.9054\times0.884 = 123.6763736\)
Contribution of D: \(141.9092\times0.111=15.7519212\)

Step3: Sum up the contributions

\(0.2718144 + 0.413724+123.6763736 + 15.7519212=140.1\)

Answer:

140.1 amu