Chlorine occurs in nature in the form of the isotopes `CI^35` (atomic mass = 34.969 amu) and `CI^37` (atomic mass = 36.966 amu) in the ratio 75.53% and 24.47%. Calculate the average atomic mass of chlorine.

Answer

To calculate the average atomic mass of chlorine based on its isotopes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Isotopes and Their Atomic Masses:**
- Chlorine has two isotopes:
- \( \text{Cl}^{35} \) with an atomic mass of 34.969 amu.
- \( \text{Cl}^{37} \) with an atomic mass of 36.966 amu.

2. **Convert Percentages to Decimal Form:**
- The abundance of \( \text{Cl}^{35} \) is 75.53%, which can be converted to decimal form:
\[ 75.53\% = \frac{75.53}{100} = 0.7553 \]
- The abundance of \( \text{Cl}^{37} \) is 24.47%, which can be converted to decimal form:
\[ 24.47\% = \frac{24.47}{100} = 0.2447 \]

3. **Calculate the Contribution of Each Isotope to the Average Atomic Mass:**
- For \( \text{Cl}^{35} \):
\[ \text{Contribution from } \text{Cl}^{35} = 0.7553 \times 34.969 = 26.41 \text{ amu} \]
- For \( \text{Cl}^{37} \):
\[ \text{Contribution from } \text{Cl}^{37} = 0.2447 \times 36.966 = 9.04 \text{ amu} \]

4. **Sum the Contributions to Find the Average Atomic Mass:**
- Now, add the contributions from both isotopes:
\[ \text{Average Atomic Mass} = 26.41 + 9.04 = 35.45 \text{ amu} \]

5. **Conclusion:**
- The average atomic mass of chlorine is \( 35.45 \text{ amu} \).