Report

Help us improve this tool

Atom Calculator

Calculate the number of protons, neutrons, and electrons in any atom or ion. Enter atomic number, mass number, and charge to find atomic composition.

O M T

What is an Atom?

An atom is the smallest constituent unit of matter that retains the properties of a chemical element. Every atom consists of a nucleus containing protons and neutrons, surrounded by a cloud of electrons. The number of protons determines the element, while the number of neutrons determines the isotope. Electrons, which orbit the nucleus, determine the atom's charge and its chemical behavior.

This atom calculator helps you determine the number of protons, neutrons, and electrons in any atom or ion. You can work in two modes: enter the atomic number (Z), mass number (A), and charge to find the atomic composition, or enter the numbers of protons, neutrons, and electrons to calculate the atomic number, mass number, and charge.

Key Concepts

  • Atomic Number (Z) - The number of protons in the nucleus. This uniquely identifies the element.
  • Mass Number (A) - The total number of protons and neutrons in the nucleus.
  • Charge (z) - The electrical charge of the atom, calculated as $Z - e$ where $e$ is the number of electrons.
  • Isotopes - Atoms of the same element with different numbers of neutrons.
  • Ions - Atoms with unequal numbers of protons and electrons, giving them a net positive (cation) or negative (anion) charge.

For more chemistry calculations, check out our Atomic Mass Calculator and Molar Mass Calculator.

Frequently Asked Questions

How do I find the number of neutrons in an atom?

To find the number of neutrons, subtract the atomic number (Z) from the mass number (A): $N = A - Z$. For example, carbon-12 has 6 protons and a mass number of 12, so it has $12 - 6 = 6$ neutrons.

What is the difference between an atom and an ion?

An atom has an equal number of protons and electrons, making it electrically neutral. An ion has an unequal number of protons and electrons, giving it a net electrical charge. A positive ion (cation) has more protons than electrons, while a negative ion (anion) has more electrons than protons.

Can an atom have more than 118 protons?

While theoretical elements beyond atomic number 118 have been predicted, no atoms with more than 118 protons have been experimentally observed. These superheavy elements are increasingly unstable and difficult to synthesize.

What gives an atom its identity?

The number of protons in the nucleus gives an atom its identity. Each element has a unique atomic number. For example, every atom with 1 proton is hydrogen, with 6 protons is carbon, and with 79 protons is gold. No two different elements have the same number of protons.

Related Tools

Remove Whitespace icon Remove Whitespace Time Duration Calculator icon Time Duration Calculator Time Calculator icon Time Calculator CTC to Inhand Calculator icon CTC to Inhand Calculator Money Calculator icon Money Calculator Siding Calculator icon Siding Calculator CSS to SASS Converter icon CSS to SASS Converter Turtle Tank icon Turtle Tank Generate Tribonacci Words icon Generate Tribonacci Words Diaper Calculator icon Diaper Calculator MDX Formatter icon MDX Formatter Add Watermark to Image icon Add Watermark to Image Text to Handwriting Converter icon Text to Handwriting Converter Next Leap Year Calculator icon Next Leap Year Calculator Wordpress Detector icon Wordpress Detector Shake 256 Hash Generator icon Shake 256 Hash Generator Percent To Rem Converter icon Percent To Rem Converter Color Desaturation icon Color Desaturation Mg to Cc Converter icon Mg to Cc Converter Point to Percent Converter icon Point to Percent Converter

Recent Visits