P3 - Particle Model of Matter

What are the three states of matter?

Solid, liquid, and gas

How are particles arranged in a solid?

Particles are close together in a fixed, regular arrangement and they vibrate on fixed positions

How are particles arranged in a liquid?

Particles are close together but in an irregular arrangement and they move around each other randomly

How are particles arranged in a gas?

Particles are spread far apart and they move rapidly and randomly in all directions

Why are solids diccicult to compress?

The particles are already very close together

Why are gases easy to compress?

There are large gaps between the particles

What does density ’ mean?

How much matter is packed into a given space

What is the equation for density?

Density = Mass ÷ volume

Why do solids usually have a higher density than liquids and gases?

Their particles are more closely packed

What is a change of state?

A change between solid, liquid and gas

What happens to the energy of a particle during melting, evaporation and boiling?

Particle gains energy

What happens to the energy of a particle during freezing and condensation?

Particles lose energy

What is evaporation?

The change of a state from liquid to a gas at any temperature

What is sublimation?

The change of state from a solid directly to a gas

What is deposition?

The change of a state from a gas directly to a solid

Why does the temperature stay constant during a change of state?

Energy is used to change the state, not to increase the particles’ kinetic energy

What is internal energy?

The total kinetic and potential energy of the particles

What happens to the internal energy when a substance is heated?

Internal energy increases

What happens to the internal energy when a substance cools?

Internal energy decreases

What is the difference between boiling and evaporation?

Boiling happens at a fixed temperature throughout the liquid, and evaporation happens at any temperature from the surface

What causes gas pressure?

Collisions of gas particles with the walls of the container

Why does gas pressure increase when the temperature increases?

Particles gain more kinetic energy so they move faster and collide with the walls more frequently and with more force

Why does the gas pressure increase when the volume decreases?

Particles collide with the walls more frequently

What are the units for pressure?

Pascals (Pa)

What is latent heat?

The energy needed to change state without changing temperature

What is specific latent heat?

The energy needed to change the state of 1 kg of a substance without changing the temperature

What is the equation for specific latent heat?

Energy = mass x specific latent heat (E = m x L)

What is specific latent heat of fusion?

The energy needed to change 1 kg from a solid to a liquid without a change in temperature

What is the specific latent heat of vaporisation?

The energy needed to change 1 kg from a liquid to a gas without a change in temperature

Density of an irregular object practical

1. Find the mass of the object using a balance
   

2. Then fill the eureka can up to the spout
   

3. Place the object into the water and this will cause water to be displaced
   

4. Measure the volume of water displaced using a measuring cylinder. This is the same volume as the object
   

5. To calculate the density use the equation Density = Mass / Volume