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Answer:
35.453 amu.
Explanation:
From the question given above, the following data were obtained:
Isotope A (Cl–35):
Abundance (A%) = 75.77%
Mass of A = 34.969 amu
Isotope B (Cl–37):
Abundance (B%) = 24.23%
Mass of B = 36.966 amu
AVERAGE atomic mass of Cl =?
The average atomic mass of Cl can be obtained as follow:
Average = [(Mass of A × A%)/100] + [(Mass of B × B%)/100]
Average = [(34.969 × 75.77)/100] + [(36.966 × 24.23)/100]
Average = 26.496 + 8.957
Average atomic mass of Cl = 35.453 amu.