1. What is the Average Atomic Mass?

The average atomic mass is the weighted average of the atomic masses of all naturally occurring isotopes of an element, taking into account their relative abundances. It's the value you see on the periodic table for each element.

2. How Does the Calculator Work?

The calculator uses the average mass formula:

Where:

• \( \text{Mass}_i \) — Mass of isotope i (in atomic mass units, amu)
• \( \text{Abundance}_i \) — Natural abundance of isotope i (percentage)

Explanation: The calculator sums the products of each isotope's mass and its fractional abundance (percentage divided by 100).

3. Importance of Average Mass Calculation

Details: Calculating average atomic mass is essential for understanding chemical properties, stoichiometric calculations, and predicting element behavior in chemical reactions.

4. Using the Calculator

Tips: Enter at least one isotope mass and its corresponding abundance. You can enter up to three isotopes. Mass values should be in amu, and abundances should be percentages (0-100%).

5. Frequently Asked Questions (FAQ)

Q1: Why don't the abundances add up to exactly 100%?
A: Natural variations and measurement uncertainties can cause slight deviations from 100%. The calculator will work with any valid percentages.

Q2: How many isotopes can I calculate with?
A: The calculator supports up to three isotopes, but you can use just one or two if needed.

Q3: What's the difference between atomic mass and mass number?
A: Mass number is the sum of protons and neutrons (a whole number), while atomic mass is the actual measured mass including decimal places.

Q4: Why is average atomic mass not a whole number?
A: It's a weighted average of different isotopes, each with slightly different masses due to nuclear binding energy differences.

Q5: Can I use this for radioactive elements?
A: Yes, but the abundances will change over time due to radioactive decay, so results are only valid for the current isotopic composition.