P3 Particle model of matter Flashcards
What is a solid?
-strong forces of attraction.
-particles held together very closely in a fixed, regular arrangement.
- particles do not have much energy and can only vibrate.
What is a liquid ?
-weaker forces of attraction.
-particles close together, but can move past each other.
-irregular arrangement.
- more energy than particles in a solid.
What is a gas?
- almost no forces of attraction between the particles.
- the most energy and are free to move in random directions.
What is the gas pressure?
When you put gas in a container the particles move around and hit the walls of the container.
What happens to the gas when the temperature rises?
The gas pressure will also increase.
The hotter the temperature, the more kinetic energy the gas particles have.
They move faster colliding with the sides of the container.
What is density?
It is a measure of how much mass there is in a given space.
What is the formula for density?
Density (kg/m3) = mass (kg) / (divided by) volume (m3)
What is the difference between more and less dense materials?
A more dense material will have more particles in the same volume when compared to a less dense material.
What is the density of an object is 8050 kg/m3 and it has a volume of 3.4m3. What is its mass in kg?
Density (kg/m3) = mass (kg) / (divided by) volume (m3)
8050 = mass / 3.4
8050 x 3.4 = mass
27370kg
What type of energy do the particles in a system have?
- kinetic energy
What is internal energy?
The total internal energy of system is the kinetic energy and the potential energy store
What happens when the system is heated?
The particles will gain more kinetic energy so increasing the internal energy.
What happens when the temperature is increase?
If heated enough then there will be enough energy to break bonds and change the state.
What happens when something changes state?
No chemical change only a physical one.
The substance will change back to its original form .
The number particles and the mass stay the same.
What is specific latent heat?
the energy required for a particular change in state
- energy being put in during boiling and melting.
What does the energy in specific latent heat do?
The energy is being used to break the bonds.
What happens when a substance is condensing or freezing?
The energy put in is used to form the bonds. This releases energy. The internal energy decreases but the temperature does not go down.
What is the energy needed to change the state of a substance called?
latent heat.
What is specific latent heat?
the amount of energy required to change the state of 1 kilogram (kg) of a material without changing its temperature.
Is specific latent heat different for different materials?
Yes
What is the specific latent heat to change a solid to a liquid?
Specific latent heat of fusion
What is the specific latent heat to change a liquid to a gas?
Specific latent heat of vaporisation
What is the Specific latent heat equation?
Energy (E) = mass (m) x specific latent heat (L)
E=ml
Required practical - Measuring the density of a regular shaped object.
What is the method?
- Measure the mass using a balance
- Measure the length, width and height using a ruler.
- calculate the volume
- use the density (p = m/v) equation to calculate.
Required practical - Measuring the density of a irregular shaped object.
- Measure the mass using a balance
- fill a eureka can with water
- Place the object in the water- the water displaced by the object will transfer into a measuring cylinder
- measure the volume of water. This equals the volume of the object
- use the density (p = m/v) equation to calculate.
