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Gwen: Introduction to Atoms
An atom is the basic building block of matter.
Atoms are made of electrons, which revolve around a nucleus, in a place called the electron cloud. Electrons are “elementary particles,” which means they are not made of any simpler parts. The nucleus is made of protons and neutrons, which in turn are made of particles called quarks. We’ll talk more about quarks in a later post.
Protons have a positive charge, and neutrons have no charge. Neutrons and protons hold each other together through a force called the strong force. If there weren’t any neutrons, the nucleus would fall apart, because protons have the same charge, so they repel each other. The neutrons help because they have strong force but they don’t have a charge.
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