2.1.1 The Particle Model

• What does the particle model help us understand?

  What matter is made of and how it behaves
• What is the name of the geometric shape shown in the image?

  Solid
• How can the state of matter be changed?

  • Increasing/decreasing temperature can cause changes between solid, liquid, and gas
  • Increasing/decreasing pressure can also cause changes between states
• How many individual elements (circles) make up the solid?

  9
• How many individual elements (circles) make up the solid?

  9
• What might the visual representation of the gas in the image be intended to convey or emphasize?

  • The distinct, circular shapes may be used to highlight the discrete, particulate nature of gases
  • The vivid coloring may be used to draw attention to the gas or make it more visually striking
• What is the relationship between particle movement and state of matter?

  Movement varies: vibrate in solids, slide in liquids, move freely in gases
• What do the red particles in the diagram represent?

  • Gas molecules
  • Bouncing around with space between them
• What is the purpose of this image in the context of the study material?

  • To illustrate the concept of a solid geometric shape
  • To show how a solid can be composed of multiple individual elements
  • To demonstrate the visual representation of a solid
• What is the name of the geometric shape shown in the image?

  Solid
• How are particles arranged in gases?

  Randomly and widely separated
• What are the characteristics of a gas state of matter?

  • No fixed shape or volume
  • Atoms/molecules are widely spaced and move randomly
  • Easily compressible and expandable
• How are particles in liquids packed together?

  Reasonably close together
• What is the name of the substance shown in the image?

  Gas
• Why do gases fill any container?

  Because particles move freely in all directions
• How does the visual representation of the gas in the image differ from how gases are typically depicted?

  • Gases are typically shown as transparent or colorless
  • The gas in the image is represented as distinct, colored circles rather than a diffuse, formless substance
• How does the arrangement of particles in a solid differ from that in a gas?

  Solids are tightly packed; gases are widely separated
• What is the shape of the individual elements that make up the solid?

  Circles
• What does the wide separation of gas particles allow?

  It allows gases to be easily compressed
• How do the particle arrangements differ between the three states of matter?

  • Solid: Particles are closely packed in a regular, ordered arrangement
  • Liquid: Particles are close together but not in a regular pattern, allowing them to flow
  • Gas: Particles are far apart and move randomly in all directions
• What are the three states of matter shown in the image?

  Solid, liquid, gas
• What is the particle motion in solids?

  Vibrate in fixed positions
• What is the particle motion in liquids?

  Slide past each other
• What is the shape of the individual elements that make up the solid?

  Circles
• How would the density of the three states of matter compare?

  • Solid: Highest density
  • Liquid: Intermediate density
  • Gas: Lowest density
• How do the particle interactions differ between the three states of matter?

  In solids, particles are tightly bound and have strong interactions. In liquids, particles have moderate interactions allowing flow. In gases, particles have weak interactions and move freely.
• What can particles in liquids do that particles in solids cannot?

  Slide past each other
• What occurs to water molecules when they boil into steam?

  They move freely with large spaces
• What does the particle model say about the spacing of particles?

  Particles are separated by empty spaces
• How would the density of the three states of matter compare?

  • Solid: Highest density
  • Liquid: Intermediate density
  • Gas: Lowest density
• What distinguishes gas particle movement from that of solids and liquids?

  • Gases: Move freely in all directions
  • Solids: Fixed positions, vibrate in place
  • Liquids: Slide past each other, less freedom
• What are the particle motions and energy levels in solids, liquids, and gases?

  • Solid:
  • Motion: Vibrate in fixed positions
  • Energy: Lowest
  • Liquid:
  • Motion: Slide past each other
  • Energy: Medium
  • Gas:
  • Motion: Move freely and randomly
  • Energy: Highest
• How do particle arrangements differ in solids, liquids, and gases?

  • Solid: Tightly packed, orderly, vibrate, very small spacing (e.g., ice cube)
  • Liquid: Closer, less organized, slide past each other, small spacing (e.g., water)
  • Gas: Widely separated, random, move freely, large spacing (e.g., steam)
• How do particles transition from solid to liquid?

  They gain energy and slide past each other
• How are particles arranged in liquids compared to gases?

  Closer than in gases
• Which state of matter has the lowest energy?

  Solid
• What keeps particles in solids in fixed positions?

  They are held in fixed positions
• Which state of matter has medium energy?

  Liquid
• How do the particle interactions differ between the three states of matter?

  In solids, particles are tightly bound and have strong interactions. In liquids, particles have moderate interactions allowing flow. In gases, particles have weak interactions and move freely.
• How are particles arranged in solids?

  In a regular pattern