Answer: Its average atomic mass is 114.9 amu
Explanation:
Mass of isotope 1 = 113 amu
% abundance of isotope 1 = 5% = [tex]\frac{5}{100}=0.05[/tex]
Mass of isotope 2 = 115 amu
% abundance of isotope 2 = 95% = [tex]\frac{95}{100}=0.95[/tex]
Formula used for average atomic mass of an element :
[tex]\text{ Average atomic mass of an element}=\sum(\text{atomic mass of an isotopes}\times {{\text { fractional abundance}})[/tex]
[tex]A=\sum[(113\times 0.05)+(115\times 0.95)][/tex]
[tex]A=114.9amu[/tex]
Thus its average atomic mass is 114.9 amu
