density

• What are the three common states of matter?

  Solids, liquids, and gases
• How are the particles arranged in solids, liquids, and gases?

  • Solids: Particles are very close together in a regular pattern.
  • Liquids: Particles are close together but not in a regular pattern and can move around each other.
  • Gases: Particles are far apart and not arranged in any pattern, moving rapidly.
• How do particles behave in a solid?

  Particles vibrate but do not move from place to place
• How do particles behave in a liquid?

  Particles can move around each other
• How do particles behave in a gas?

  Particles are moving very rapidly
• What does the density of a material tell us?

  The mass for a given volume
• How is density calculated?

  Density equals mass divided by volume
• What is the unit of density?

  Kilograms per meter cubed
• If a block of wood has a mass of 150 kilograms and a volume of 0.3 meters cubed, what is its density?

  500 kilograms per meter cubed
• Why do solids usually have a high density?

  • Particles are packed closely together
  • Solids have a lot of mass for their volume
• Why do liquids usually have a high density?

  • Particles are close together
  • Liquids have a lot of mass for their volume
• Why do gases have a low density?

  • Particles are very far apart
  • Gases have a small mass for their volume
• What is an exception to the general rule about solid density?

  Polystyrene has a low density despite being a solid
• Why does polystyrene have a low density?

  It has a very open structure filled with air spaces