Electroscope Lab

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Electroscope Lab
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Before the Lab

• What did the leaves look like?
• Hanging straight down.
• What is making them stay in that position?
• Gravity

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So.What did you observe?

• What happened to the leaves when you touched the
  ball after being rubbed on the fabric?
• They Spread apartWhat happened to the rods when
  they were rubbed with the fabric?
• They became either positively or negatively
  charged.

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Observations.

• Why did the leaves spread apart?
• Electrons were transferred off or on the rod.
• What happened when you touched the ball of the
  electroscope?
• The leaves returned to their natural position
• Electrons transferred to or from the rod to your
  finger
• to be neutral
• Neutral---equal electrons and protons
• Everything wants to be neutral

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Observations cont

• Which piece of fabric added electrons to the rod?
• Wool---which gave the white rod a negative
  charge
• Which piece of fabric took electrons away from
  the rod?
• Silk---which gave the clear rod a positive charge

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Observations.

• How do we know that one piece of fabric made the
  rod have a positive charge and the other have a
  negative charge?
• Part D of the activity
• The leaves moved closer when the white rod was
  close to the ball of the electroscope.
• Started to become Neutral
• If they were both negative/positive the leaves
  would have gotten farther apart.

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Conclusion

• What is the name of this force that pushes the
  leaves apart by transfering electrons?
• Electrostatic Force
• What can we infer from this lab?
• Opposite charges attract
• Like charges repell
• The charge extends beyond the particle
• This is the 2nd strongest force in the atom

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• Elements
• Cant be divided into any simpler substances.
• Atoms
• Smallest particle of an element that still have
  all the properties of that element.

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• Subatomic Particles
• Proton() charge, nucleus
• Neutron(0) charge, nucleus
• Electron(-) charge, electron cloud

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Elements and Atoms

• 90 naturally occurring elements
• 20 synthetic elements
• What is synthetic?
• Man made