Final answer:
The average atomic mass of chlorine is calculated by multiplying the percent abundance of each isotope by its atomic mass and adding these contributions together. After calculating and rounding to two decimal places, it is 35.45 amu.
Step-by-step explanation:
The student has asked about the average atomic mass of chlorine atoms, considering the natural abundance of its isotopes. To calculate it, we use the available abundance and atomic mass data for each isotope.
- Calculate the mass contribution of Chlorine-35 to the average atomic mass:
(0.7577 × 34.969 amu) = 26.495463 amu
- Calculate the mass contribution of Chlorine-37 to the average atomic mass:
(0.2423 × 36.966 amu) = 8.957958 amu
- Add the contributions of both isotopes to get the average atomic mass:
26.495463 amu + 8.957958 amu = 35.453421 amu
After calculating the values and adding them up, we find that the average atomic mass of chlorine, when rounded to two decimal places as per significant figure rules, is 35.45 amu.