Structure of an Atom: Sub-atomic Particles

 

                    

What Is an Electron?

An electron is a tiny, negatively charged particle that is part of every atom. Electrons move around the nucleus of an atom, which contains protons and neutrons. Even though electrons are much smaller than protons and neutrons, they play a huge role in how atoms behave and how elements react.

Key Facts About Electrons:

• Charge: Negative (−1)

• Mass: Very small—about 1/1836 the mass of a proton

• Location: Found in energy levels or shells outside the nucleus

• Movement: They move rapidly around the nucleus in regions called electron clouds

• Role: Electrons are responsible for electricity, chemical bonding, and reactions

Why Electrons Matter:

• They determine how atoms bond with each other (e.g., in covalent or ionic bonds).

• The number of electrons equals the number of protons in a neutral atom.

• When electrons move from one atom to another, electricity is created!

  

  
  

  What Is a Proton?

  A proton is a positively charged particle found in the nucleus (center) of an atom. Along with neutrons, protons make up most of an atom’s mass. The number of protons in an atom determines what element it is—for example, hydrogen has 1 proton, helium has 2, and so on.

  Key Facts About Protons:

  • Charge: Positive (+1)

  • Mass: About 1 atomic mass unit (same as a neutron)

  • Location: Inside the nucleus of the atom

  • Symbol: p⁺

  • Role: Defines the element and helps balance the charge with electrons

  Why Protons Matter:

  • The atomic number of an element equals the number of protons in its atoms.

  • Protons help hold the nucleus together through the strong nuclear force.

  • The number of protons determines an atom’s identity and place on the periodic table.

                                                         What Is a Neutron?

A neutron is a particle found in the nucleus of an atom, alongside protons. Unlike protons and electrons, neutrons have no electric charge—they are neutral. Neutrons help add mass to the atom and play a key role in keeping the nucleus stable.

Key Facts About Neutrons:

• Charge: Neutral (0)

• Mass: About the same as a proton (1 atomic mass unit)

• Location: Inside the nucleus

• Symbol: n⁰

• Role: Helps stabilize the nucleus and adds to the atom's mass

Why Neutrons Matter:

• Without neutrons, the nucleus would be unstable due to repelling positive charges from protons.

• Different numbers of neutrons in the same element create isotopes (e.g., Carbon-12 vs Carbon-14).

• Neutrons are important in nuclear reactions and energy production.

watch this youTube video to learn more..

About the Author

Yusuf Almustapha Muhammad is a Chemistry educator with a passion for making science simple and engaging for students. Through Chemysteries Unraveled, he shares clear explanations of chemistry concepts, study resources, and practical insights to support learners and fellow educators.

Connect with me on LinkedIn for more educational content and updates.

linkedin.com/in/yusuf-almustapha-chemistry