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:

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

Explanation: The equation calculates the 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 and appears on the periodic table. It's essential for stoichiometric calculations in chemistry.

4. Using the Calculator

Tips: Enter the percentage abundance (must sum to 100% for accurate results) and mass for each isotope. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why don't percentages add up to 100% on the periodic table?
A: Some elements have very rare isotopes that aren't always listed. The calculator can handle any number of isotopes.

Q2: How precise should my inputs be?
A: For classroom problems, 2-4 decimal places are usually sufficient. For research, use more precise measurements.

Q3: Can I calculate for more than two isotopes?
A: Yes, simply add the contributions of additional isotopes using the same formula.

Q4: Why is average atomic mass not a whole number?
A: It's a weighted average of different isotope masses, which rarely results in a whole number.

Q5: How does this relate to molar mass?
A: The average atomic mass in amu is numerically equal to molar mass in g/mol.