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Atom Calculator

Calculate atomic properties, electron configurations, and explore atomic structure with our comprehensive atomic calculator

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Understanding Atomic Structure

Atoms are the fundamental building blocks of matter. Our calculator helps you explore atomic properties, determine electron configurations, and understand atomic structure through interactive calculations and visualizations.

Atomic Structure Calculator

Calculate atomic properties and electron configuration

Atomic Structure Guide

Nucleus

The dense central region of an atom containing protons and neutrons

  • Contains protons (positive charge)
  • Contains neutrons (neutral charge)
  • Most of the atom's mass
  • Very small volume

Electron Shells

Regions around the nucleus where electrons are likely to be found

  • Electrons orbit in shells
  • Each shell has a maximum capacity
  • Shells fill from inside out
  • Determines atomic size

Valence Electrons

Electrons in the outermost shell that participate in chemical bonding

  • Determines chemical properties
  • Involved in bonding
  • Maximum of 8 electrons
  • Defines oxidation state

Frequently Asked Questions

What is atomic number?

The atomic number is the number of protons in an atom's nucleus. It defines the element and determines its chemical properties. All atoms of the same element have the same atomic number.

How is mass number calculated?

Mass number is the total number of protons and neutrons in an atom's nucleus. It can be calculated by adding the number of protons (atomic number) and the number of neutrons.

What are electron shells?

Electron shells are energy levels around an atom's nucleus where electrons are found. Each shell can hold a specific maximum number of electrons, following the 2n² rule, where n is the shell number.

What are valence electrons?

Valence electrons are the electrons in the outermost shell of an atom. They determine the atom's chemical properties and how it bonds with other atoms. Most atoms are most stable with 8 valence electrons.

How is electron configuration written?

Electron configuration shows how electrons are distributed in atomic orbitals. It uses numbers and letters (1s, 2s, 2p, etc.) to indicate the shell and subshell, followed by the number of electrons in that subshell.

Important Notes

  • Atomic number determines the number of protons in the nucleus
  • Mass number is the sum of protons and neutrons
  • Electron configuration follows the Aufbau principle
  • Valence electrons determine chemical properties
  • Isotopes have the same atomic number but different mass numbers
  • The periodic table organizes elements by atomic structure