density and matter

• density is the measure of...

  compactness of a substance
• density (kg/m³) =


  mass (kg) / volume (m³)
• density formula


  ρ=m/v
• density formula triangle

  
• the density of an object depends on...

  what it's made of/type of material
• a dense object has particles...

  packed tightly together
• a less dense object has particles...


  more spread out
• general order of density of states of matter

  solids > liquids > gases
• particles in a system vibrate or are in constant motion because...

  they have energy in their kinetic stores
• heating a system transfers energy to...

  its particles, increasing their kinetic stores and resulting in increased internal energy
• increased internal energy results in...

  change in temperature/state
• if the temperature of a system changes...

  the size of the change will depend on its mass
• a change in state of a system occurs if...

  a substance is heated enough, allowing the particles to have enough energy in their kinetic energy store to break the bonds holding them together
• change of state conserves...

  mass
• average energy in kinetic stores is related to...

  temperature
• when a substance heats up...

  energy is being put in to break bonds between the particles
• change of state graph (heating)

  
• when a substance is cools down...

  bonds are forming between the particles, releasing energy
• change of state graph (cooling)

  
• specific latent heat is...

  amount of heat needed to change the state of 1kg of a substance without a change in temperature
• specific latent heat is different for...

  different materials and for changing between different states
• specific latent heat (L) =

  energy (J) / mass (kg)
• specific latent heat formula

  L=E/m
• specific latent heat formula triangle

  
• colliding gas particles create...

  pressure
• how does gas particles colliding create pressure?

  faster particles and more frequent collisions both lead to an increase in net force, and so gas pressure as the collisions exert a force on the particles in collisions
• what is a way of increasing speed of particles in a gas?

  by heating them up
• increasing the volume and keeping the temperature of a gas the same results in...

  the particles spreading out, reducing the amount of collisions making the pressure decrease
• Boyle's law


  a principle that describes the relationship between the pressure and volume of a gas at constant temperature (pV=constant)
• if the pressure is changed in a gas...

  volume is also changed, this is because the change will cause the gas to compress or expand to adapt to the changed container pressure/size
• if work is done on a gas...

  the temperature increases, this is because internal energy is increased due to increased kinetic energy stores of the gas particles transferring to the thermal energy stores