Simulations & Videos for

Lesson 4.1: Protons, Neutrons, and Electrons

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Pencil Zoom

  • The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms.
  • The picture shows a close-up of one carbon atom.

Interactive
Protons & Electrons

  • Protons have a positive charge. Two protons repel each other.
  • Electrons have a negative charge. Two electrons repel each other.
  • A proton and an electron have opposite charges and attract each other.

Interactive
Hydrogen Atom

  • A hydrogen atom has one proton as the nucleus and one electron in the region outside the nucleus.
  • The electron and proton are attracted to each other. This attraction holds the atom together.
  • It is not possible to locate the exact position of an electron, but the electron cloud shows the region where an electron is most likely to be.
Molecule diagram of Plastic and Hand

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Charged Plastic and Hand

  • When the plastic strip is rubbed on the skin, electrons from the skin are transferred to the plastic giving the plastic a negative charge.
  • When the plastic is moved near the desk, electrons in the desk are repelled by the negatively charged plastic.
  • This leaves an area of positive charge in the desk near the plastic.
  • The negative plastic and the positive area of the desk attract.

Youtube ID: XoxZqeaiykM

Video
Balloon and Water

  • When the balloon is rubbed on hair or clothes, electrons move onto the balloon giving it a negative charge.
  • When the negatively charged balloon is brought near the water, electrons are repelled and move away from the balloon, leaving a positive area of the water near the balloon.
  • The negatively charged balloon and the positive area of the water attract.