1. What is Average Atomic Mass?

The average atomic mass is the weighted average of the atomic masses of all naturally occurring isotopes of an element. It accounts for both the mass and relative abundance of each isotope.

2. How Does the Calculator Work?

The calculator uses the average atomic mass formula:

Where:

• \( \text{abundance} \) — Natural abundance of each isotope (%)
• \( \text{isotope} \) — Atomic mass of each isotope (amu)

Explanation: The equation calculates a weighted average where more abundant isotopes contribute more to the final average mass.

3. Importance of Average Atomic Mass

Details: The average atomic mass is crucial for chemical calculations, stoichiometry, and understanding element properties. It's the value shown on the periodic table for each element.

4. Using the Calculator

Tips: Enter the mass of each isotope in atomic mass units (amu) and their natural abundance in percentage. The sum of abundances should not exceed 100%.

5. Frequently Asked Questions (FAQ)

Q1: Why isn't atomic mass a whole number?
A: Atomic mass isn't a whole number because it's an average of different isotopes, each with different masses and abundances.

Q2: How many isotopes can I calculate for?
A: This calculator handles two isotopes. For more isotopes, you would need to extend the calculation similarly.

Q3: What's the difference between mass number and atomic mass?
A: Mass number is the sum of protons and neutrons (always a whole number), while atomic mass is the weighted average of all isotopes.

Q4: Why do we use weighted average?
A: A weighted average accounts for the fact that some isotopes occur more frequently in nature than others.

Q5: Can I use this for radioactive elements?
A: For radioactive elements with very short half-lives, the natural abundances may vary, affecting the accuracy of the calculation.