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Atom Definition

An atom is the basic unit of an element, and is made of protons, neutrons, and electrons. Atoms combine to form molecules, like water.

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Atoms & Molecules

Fun Facts

  • Atoms are more than 10,000 times smaller than the width of a human hair.
  • A Scanning Tunneling Microscope can show individual atoms.
  • DNA is made from atoms.

Why Do We Need To Know About Atom

Learning about atoms helps us understand what everything is made of and is important for creating new medicines.  Doctors use this knowledge to make new drugs that can mimic the good stuff in our bodies to fight off diseases for people who are missing them.

Chemists study atoms and how to put them together. By learning about atoms, we know why we need certain elements, like iron, to stay healthy. This shows us how eating a variety of foods keeps us in good shape.

Frequently Asked Questions

What would you see if you looked at iron filings with a Scanning Tunneling Microscope?
Since the Scanning Tunneling Microscope is so powerful, you would see tiny spheres which are iron atoms (the smallest possible unit of iron).
Describe the different particles that make up an atom.
An atom is made up of 3 particles; protons, neutrons and electrons. Protons are positively charged and are positioned in the center of an atom. Neutrons are not charged and are also located in the center of an atom. Electrons orbit the center very quickly and are negatively charged.
What are some examples of elements? How do you know they are elements?
Some examples of elements are gold, iron, copper and carbon. Anything on the periodic table is an element. All elements are pure substance made up of only one type of atom.
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