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Molecule Definition

A molecule is two or more atoms bonded together. For example, a water molecule (H2O) is two hydrogen atoms bonded to one oxygen atom.

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Atoms & Molecules

Fun Facts

  • An ammonia molecule is made of one nitrogen atom and three hydrogen atoms.
  • A molecule of sucrose consists of 12 carbon, 22 hydrogen, and 11 oxygen atoms.
  • A molecule is the smallest particle of a substance with all the properties of the substance.

Why Do We Need To Know About Molecule

Learning about molecules helps us understand the basics of life.  Molecules are key in making new medicines and knowing how our bodies work.

For example, scientists make molecules like insulin to help people with diabetes. Also, researching molecules leads to new ways to fight diseases, like cancer.

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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