Question

Isotope ⁷⁹br has an abundance of 50.69%

isotope ⁸¹ br has an abundance of 49.31%
ar of bromine=..........................

Answer 1

79.986

Explanation:

Let A represent isotope ⁷⁹Br

Let B represent isotope ⁸¹Br

From the question given above, the following data were obtained:

For Isotope A (⁷⁹Br):

Mass of A = 79

Abundance of A (A%) = 50.69%

For isotope B (⁸¹Br):

Mass of B = 81

Abundance of B (B%) = 49.31%

Relative atomic mass of Br =?

The relative atomic mass (RAM) of Br can be obtained as follow:

RAM = [(Mass of A × A%) /100] + [(Mass of B × B%) /100]

= [(79 × 50.69) /100] + [(81 × 49.31) /100]

= 40.0451 + 39.9411

= 79.986 amu

Thus, the relative atomic mass of Br is 79.986