To calculate the atomic mass of sulfur based on the given isotopes and their respective abundances, we can use the formula:
\[ \text{Atomic Mass} = \sum (\text{isotope mass} \times \text{fractional abundance}) \]
We'll first convert the percentages of abundance into fractional form by dividing by 100:
- For the first isotope (31.972 amu) with 95.00% abundance, the fractional abundance is \(0.9500\).
- For the second isotope (32.971 amu) with 0.76% abundance, the fractional abundance is \(0.0076\).
- For the third isotope (33.967 amu) with 4.22% abundance, the fractional abundance is \(0.0422\).
- For the fourth isotope (35.967 amu) with 0.014% abundance, the fractional abundance is \(0.00014\).
Now we calculate the contribution of each isotope to the atomic mass:
- \(31.972 , \text{amu} \times 0.9500 = 30.3734 , \text{amu}\)
- \(32.971 , \text{amu} \times 0.0076 = 0.2506 , \text{amu}\)
- \(33.967 , \text{amu} \times 0.0422 = 1.4325 , \text{amu}\)
- \(35.967 , \text{amu} \times 0.00014 = 0.005036 , \text{amu}\)
Now, we sum these contributions:
\[ \text{Atomic Mass} = 30.3734 + 0.2506 + 1.4325 + 0.005036 \]
Calculating the sum:
\[ \text{Atomic Mass} = 32.061536 , \text{amu} \]
Rounding to appropriate significant figures, the atomic mass of sulfur is approximately:
\[ \text{Atomic Mass} \approx 32.06 , \text{amu} \]
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