What is an atom?

An atom is a “a fundamental piece of matter”, matter being defined as “anything that can be touched physically.”  Everything that you can touch is therefore made up of atoms.


Look around you!  Your desk, computer, pencil, notebook, folder, binder, and eraser are made up of atoms.  Even you are made up of atoms!


Every atom is made up of protons, neutrons, and electrons.  Protons have a positive charge, electrons have a negative charge, and neutrons are neutral (neither positive nor negative).  The mass of one proton is 1 amu (atomic mass unit.)  The mass of one neutron is also 1 amu.  The mass of one electron is so small that it is not measured.


Protons and neutrons are in the center of the atom in a place called the nucleus.  The electrons are above the nucleus in a small cloud.

 

Wordle: Atoms

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