3.3- particle model and pressure

• What is the motion of molecules in a gas?

  They are in constant random motion.
• What effect does increasing temperature have on the pressure of a gas at constant volume?

  Pressure of the gas will increase.
• What factor affects the average kinetic energy of gas molecules?

  The temperature of the substance.
• How does temperature relate to the average kinetic energy of gas molecules?

  The higher the temperature, the higher the average kinetic energy.
• Why does pressure increase as temperature increases at constant volume?

  Kinetic energy of molecules increases.
• What happens to collisions between molecules as temperature increases?

  Collisions become more frequent.
• What is the effect of increased momentum change on pressure?

  Greater force results in greater pressure.
• How does the pressure of a gas exert force on the walls of its container?

  The net force acts at right-angles to the surface.
• What happens to the force exerted by a gas as pressure increases?

  The force increases as pressure increases.
• How does increasing the volume of a gas affect pressure?

  Molecules become more spread out.
• What happens to the time between collisions when volume increases?

  Time between collisions increases.
• How does the rate of collisions change with increased volume?

  This reduces the rate of collisions.
• What happens to the rate of change of momentum when volume increases?

  Rate of change of momentum decreases.
• What is the relationship between force exerted on the container and pressure?

  Force exerted decreases, resulting in lower pressure.
• If gas A is at low pressure and gas B is at high pressure, what can be said about their collision rates?

  More collisions per second in gas B.
• What is the unit used for pressure?

  Pascal (Pa)
• What can be said about the product of pressure and volume for a fixed mass of gas at constant temperature?

  It is constant.
• What is the formula that represents the relationship between pressure and volume?

  $p V =$$constant$
• What increases when work is done on a gas?

  The internal energy of the gas.
• What can happen to the temperature of a gas when work is done on it?

  This can lead to an increase of temperature.
• Why does the temperature of air inside a bike pump increase when it is pumped?

  Work is done on a gas when compressed.
• How does doing work on a gas affect its internal energy?

  It increases the internal energy.
• What happens to the average kinetic energy of molecules when internal energy increases?

  Average kinetic energy of molecules increases.
• How does temperature relate to average kinetic energy?

  Temperature increases with average kinetic energy.