Scientists Say: Bond

This is a semi-permanent attachment between atoms

the molecular structure of caffeine

This is a model of the molecule caffeine — the drug that keeps drinkers of coffee, tea and soda alert. In this model, the balls represent atoms, and the sticks represent the chemical bonds — the connections between the atoms.

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Bond (noun, “BOND”)

In chemistry, a bond is an attachment between atoms. Bonds form because atoms are made of particles with electrical charges. The center of an atom contains particles with a positive charge, and particles with no charge. The particles around the outside of an atom each have a negative charge. Have you heard the saying “opposites attract?” It applies in chemistry, too. The attraction between negative charges in one atom and positive charges in another is the basis for a chemical bond

Chemical bonds between individual atoms form molecules. Bonds can also form between the atoms in molecules and other atoms or molecules nearby. Chemical bonds form every solid thing on Earth — from huge boulders to the cells in your body.

There are many kinds of chemical bonds. All of them require energy to form, and energy to break. Every chemical reaction involves a change in chemical bonds as atoms get added or removed from molecules. That’s why all chemical reactions involve energy.

In a sentence

Bonds between hydrogen atoms might help explain why hot water freezes faster than cold water.

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Bethany Brookshire was a longtime staff writer at Science News Explores and is the author of the book Pests: How Humans Create Animal Villains. She has a Ph.D. in physiology and pharmacology and likes to write about neuroscience, biology, climate and more. She thinks Porgs are an invasive species.

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