Y7 Physics 1 : States of matter

• What is the main topic of the study material?

  Energy and states of matter in physics
• What is density?

  Density is how heavy something is for its size
• What happens during diffusion?


  Diffusion is when particles move from a place of high concentration to low concentration
• How can diffusion be made faster?


  Diffusion can be faster with increased temperature and agitation
• What are the states of matter and their transitions?

  • Solid to liquid: melting
  • Solid to gas: sublimation
  • Liquid to gas: evaporation
  • Gas to liquid: condensation
  • Gas to solid: deposition
• What is the relationship between density and gravity?


  Density is affected by how much mass is pulled down by gravity
• Which state of matter has the least density?


  Gas
• How does the density of liquids compare to solids?


  Liquids are generally less dense than solids
• What happens to gas particles in terms of density?


  Gas particles spread out and move independently
• What causes pressure in a gas?


  Pressure is caused when particles collide with the sides of their container
• How does the number of particles affect pressure?


  The more particles there are, the more pressure is created
• What happens to gas particles when they condense into a liquid?


  The particles move slower during condensation
• What is atmospheric pressure?

  Atmospheric pressure is the weight of the air above us
• What is an exception to the general rule of density?


  Water is less dense as a solid (ice) than as a liquid
• How can density vary?


  Density can vary depending on the type of atoms present
• What is the relationship between pressure and temperature?


  More heat generally leads to more pressure
• What happens to pressure when volume increases?


  When volume increases, pressure decreases
• What is the formula for density?

  Density = mass/volume
• What is the effect of pressure on the shape of a gas?


  Pressure can change the shape of a gas within its container
• How does the density of a substance affect its buoyancy?


  Less dense substances float while denser substances sink
• Pressure formula?


  Pressure = force/ area
• Why does cooling decrease pressure?

  The particles move slower and cannot hit the edges as fast. The pressure outside would be greater than that inside.
• What causes a gas to burst out of its container? E.g a balloon.


  When the pressure on the inside greater than that outside.
• What decreases when pressure increases?


  Oxygen decreases. (volume.)