Respuesta :
Answer: The average atomic mass of element bromine is 80.4104 amu.
Explanation:
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
[tex]\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i[/tex] .....(1)
- For _{35}^{79}\textrm{Br}[/tex] isotope:
Mass of [tex]_{35}^{79}\textrm{Br}[/tex] isotope = 78.9183 amu
Percentage abundance of [tex]_{35}^{79}\textrm{Br}[/tex] isotope = 50.69 %
Fractional abundance of [tex]_{35}^{79}\textrm{Br}[/tex] isotope = 0.5069
- For [tex]_{35}^{81}\textrm{Br}[/tex] isotope:
Mass of [tex]_{35}^{81}\textrm{Br}[/tex] isotope = 80.9163 amu
Percentage abundance of [tex]_{35}^{81}\textrm{Br}[/tex] isotope = 49.31 %
Fractional abundance of [tex]_{35}^{81}\textrm{Br}[/tex] isotope = 0.4931
Putting values in equation 1, we get:
[tex]\text{Average atomic mass of Bromine}=[(78.9183\times 0.5069)+(80.9163\times 0.4931)][/tex]
[tex]\text{Average atomic mass of Bromine}=80.4104amu[/tex]
Hence, the average atomic mass of element bromine is 80.4104 amu.
