P3 - Particle Model of Matter Flashcards
What is the definition of density and what is the equation to calculate it?
Density is the mass per unit volume.
Density = mass ÷ volume
The units for density are kg/m³ OR g/cm³
How do you use a Eureka can to measure volume?
1 - Fill a Eureka can to the top
2 - Place an object inside it
3 - Measure the volume of water that comes out of the eureka can
What are the most important things to remember about the particles in a liquid?
The particles in a liquid are still touching and they are free to move
(A little bit like a children’s ball pit)
Describe what is happening at points A, B, C, D and E on the graph.
Temp
| /
| E /
| __D__ /
| /
| C /
| __B__ /
| /
| A
|/_________________________ Time
A - Solid is being heated
B - Solid melts
C - Liquid is being heated
D - Liquid boils
E - Gas is being heated
What is the definition internal energy?
Internal energy of a substance is the sum of the potential energy of the particles and kinetic energy of the particles
What happens if you change the kinetic energy of the particles in a substance?
The temperature will change.
Increasing the kinetic energy will increase the temperature
What happens if you change the potential energy of the particles in a substance?
When you change the potential energy of a substance you are changing the positions of the particles.
In reading or decreasing the potential energy will cause a change of state
What is the specific latent heat of fusion and vapourisation of a substance?
Fusion - The energy needed to melt/freeze 1kg of a substance without changing the temperature
Vapourisation - The energy needed to evaporate/condense 1kg of a substance without changing the temperature.
What causes pressure in a gas?
1 - Particles move randomly
2 - They collide with the walls of the container
3 - This applies a force to the walls
4 - The pressure is the amount of force per unit area
