P1- Particle model of matter Flashcards
Density
The measure of the ‘compactness’ of substance. Tells you how much mass is packed into a given volume of space.
Density equation
Mass(kg/g) / Volume(cm3/m3)
Method to determine the density of a regular object
Measure mass using a balance, measure the sides of the block using a ruler, calculate the volume using l x w x h and use the density equation to work out the density
Method to determine the density of an irregular object
Measure mass of irregular object with a balance. Fill the eureka can with water up to the spout, carefully submerge the object into the water (lower using string), collect displaced water into a measuring cyclinder, displaced water= volume of object, use density equation
Method to determine the density of a liquid
Place measuring cylinder on a balance, zero balance reading, pour in a volume of liquid, read off the scale (1ml=1cm3), record mass of balance in grams, use density equation (mass/volume)
Arrangement of particles in a solid
Regular
Arrangement of particles in a liquid
Irregular
Arrangement of particles in a gas
Random
Is there space between the particles in a solid
No
Is there space between the particles in a liquid
No
Is there space between the particles in a gas
Yes
Movement of particles in a solid
Vibrate about fixed positions
Movement of particles in a liquid
Move loosely around eachother
Movement of particles in a gas
Move in random speeds in random directions
Forces of attraction between particles in a solid
Strong
Forces of attraction between particles in a liquid
Weakened (bonds have loosened)
Forces of attraction between particles in a gas
Virtually zero
Density of a solid
High
Density of a liquid
Medium
Density of a gas
Low
If an object is more dense than the liquid it is in, what will happen
It will sink
If an object is less dense than the liquid it is in, what will happen
It will float
What kind of changes are state changes
Physical changes, they can be reversed
What will mass always be in a state change
Conserved (the same)
Does temperature change in a state change
No, the energy goes into creating and breaking the bonds
3 limitations of the particle models
They assume particles are all spherical, they are only 2D and no movement or vibrations are shown
What is internal (thermal) energy
The energy stored by the particles making up a system
What does heating a system do
It transfers energy to its particles which increases the internal energy and leads to a change in temperature or state
When does a change of state occur
If a substance is heated enough
Solid to liquid process
Melting
Liquid to gas process
Evaporation
Gas to liquid process
Condensation
Solid to gas process
Sublimation
Liquid to solid process
Freezing
What is Specific Latent Heat
The amount of energy required for 1kg of mass to change state
What is Specific Latent Heat of Fusion
The specific latent heat (energy needed for 1kg of a substance) for changing between a solid and a liquid
What is Specific Latent Heat of Vapourisation
The specific latent heat (energy needed for 1kg of a substance) for changing between a liquid and a gas
Equation for energy for a change of state
Energy for a change of state= mass x specific latent heat
If you increase the temperature of a gas, what happens
You transfer energy into the kinetic energy stores of its particles, meaning the speed of the particles increase and also the pressure
What does colliding gas particles create
Pressure
What is the relationship between pressure and volume
Inversely proportional
What does doing work on a gas increase
Temperature
Pressure equation
Pressure= Force/ Area
Pressure and volume equation
Pressure x Volume = Constant
