1. What is Atomic Mass?

Atomic mass (also called atomic weight) is the total mass of protons and neutrons in an atom, measured in atomic mass units (amu). It's approximately equal to the mass number of the atom.

2. How Does the Calculator Work?

The calculator uses the atomic mass formula:

Where:

• Protons — Positively charged particles in the nucleus
• Neutrons — Neutral particles in the nucleus
• 1 amu — Approximately 1.660539 × 10⁻²⁷ kilograms

Explanation: The mass of electrons is negligible in this calculation as they are much lighter than nucleons (protons and neutrons).

3. Importance of Atomic Mass Calculation

Details: Knowing the atomic mass is essential for chemical calculations, understanding isotopes, and predicting an element's behavior in chemical reactions.

4. Using the Calculator

Tips: Enter the number of protons (atomic number) and neutrons. The calculator will sum them to give the atomic mass in amu.

5. Frequently Asked Questions (FAQ)

Q1: Why don't we include electron mass?
A: Electrons have negligible mass (about 1/1836th of a proton's mass) compared to nucleons, so their contribution is typically ignored.

Q2: What's the difference between mass number and atomic mass?
A: Mass number is the sum of protons and neutrons (an integer), while atomic mass is the weighted average of all isotopes' mass numbers.

Q3: Why do atomic masses in the periodic table have decimals?
A: The values in the periodic table are weighted averages accounting for all naturally occurring isotopes and their abundances.

Q4: How accurate is this simple calculation?
A: This gives the mass number for a specific isotope. For precise chemical calculations, use the exact isotopic mass or periodic table values.

Q5: What about the mass defect?
A: Nuclear binding energy causes the actual mass to be slightly less than the sum of nucleons, but this difference is typically negligible for most calculations.