P2 solids, liquids and gases

• What is meant by a state of matter?

  A form in which matter can exist
• Name the 3 different states of matter.

  Solid, Liquid, Gas
• Order the 3 states of matter by kinetic energy.

  Solid, Liquid, Gas
• How does kinetic theory explain the structure of liquids?

  Particles have some kinetic energy and move randomly
• Explain the movement of particles in a solid.

  Particles vibrate around a fixed position
• What is the difference between particles in a gas and a solid?

  Gases have no forces between particles; solids do
• Which state of matter has the highest density and why?

  Solids, because particles are tightly packed
• Does a gas have a high or low density and why?

  Low density, particles are very spread out
• Why is a liquid described to have a moderate density?

  Particles are tightly packed but can slide
• Name physical changes that don’t change the mass of a substance.

  Melting, Freezing, Boiling, Evaporating, Condensing
• Why does heating increase the temperature of a substance?

  It increases the average kinetic energy of particles
• How does heating cause a substance to change state?

  Thermal energy breaks bonds at specific temperatures
• What is specific heat capacity?

  Energy to raise 1 kg by 1°C
• What equation calculates energy required to change temperature?

  Change in thermal energy = mass × specific heat capacity × change in temperature
• How can unwanted energy transfer while heating be reduced?

  By using insulation to prevent energy loss