States of matter

• What are the three states of matter?

  Solid, liquid, and gas
• What determines the state of a substance at a certain temperature?

  The strength of attraction between particles
• What factors affect the strength of forces between particles?

  Material, temperature, and pressure
• What is particle theory used for?

  • Explains behavior of particles in states of matter
  • Considers particles as small molecules
• How are particles arranged in solids?

  In a fixed lattice arrangement
• What happens to particles in solids when heated?

  They vibrate more and expand slightly
• What is the arrangement of particles in liquids?

  Free to move past each other
• How do liquids behave in terms of shape and volume?

  Definite volume but no definite shape
• What causes liquids to expand when heated?

  Particles move faster with increased temperature
• How are particles arranged in gases?

  Far apart and free to move
• What happens to gases when heated?

  They move faster and may expand
• What is the significance of state symbols in chemical equations?

  They indicate the physical state of substances
• What does (s), (l), (g), and (aq) represent in state symbols?

  Solid, liquid, gas, aqueous
• What happens to a solid when it reaches its melting point?

  It turns into a liquid
• What is the process called when a liquid becomes a gas?

  Boiling or evaporating
• What occurs during freezing?

  A liquid turns into a solid
• What is the boiling point?

  The temperature at which a liquid becomes a gas
• How does energy affect the state changes of substances?

  More energy is needed to break stronger forces
• How can you predict the state of a substance at a certain temperature?

  Compare temperature to melting and boiling points
• Which substance is a liquid at room temperature from the example given?

  Bromine
• Why does bromine exist as a liquid at room temperature?

  It has a melting point above and boiling point below 25 °C