PARTICLE MODEL OF MATTER Flashcards
What are the particles in a dense material arranged like?
Particles are packed tightly together
What are the particles in a less dense material arranged like?
Particles are more spread out
What happens when you compress a material?
The particles move closer together (mass doesn’t change)
What are the particles like in a solid?
Fixed regular arrangement
Strong forces of attraction
Particles only vibrate (not much energy)
High density
What are the particles like in a liquid?
Weaker forces of attraction
Particles are close together but can move mast each other
Form irregular arrangements
Less dense and more energy than solids
What are the particles like in a gas?
No forces of attraction
Lots of energy (free to move)
Low density
How do you find the volume of an irregular object?
Submerge it in a eureka can filled with water
Water displaced goes into measuring cylinder
Why do materials have energy in their kinetic energy store?
Particles in the material vibrate or move around
What is the internal energy of a system?
The total energy stored by its particles in their kinetic and potential energy stores
What happens when you heat a system?
Transfers energy to its particles so increases the internal energy
When does a change in state occur?
When the substance is heated enough so the particles have enough energy in their kinetic energy stores to break the bonds holding them together
What is it called when you go from a solid to a gas?
Sublimating
What happens when a substance changes state due to cooling?
The particles lose energy and form bonds
What is latent heat?
The energy needed to change the state of a substance
What is specific latent heat?
The amount of energy needed to change 1kg of a substance from one state to another without changing its temperature
What happens when you increase the temperature of a gas?
Increases energy in the kinetic energy stores
So increases average speed of particles
What happens to the pressure of a gas when the temp is increased?
Faster particles so more frequent collisions so increases pressure
What happens to a gas if the temperature is constant but the volume is increased?
The pressure decreases as particles are more spread out
What is the pressure of a gas?
The total force exerted by all of the particles in the gas on a unit area of the container walls
How do pressure and volume of a gas relate?
They are inversely proportional
What happens to the volume of a gas when the pressure is increased?
Cause container to expand or compress due to change in force on outside or inside
How does doing work on a gas increase temperature?
Increases its internal energy so energy transferred to kinetic energy store
Increases temp
How are the temperature, pressure and volume of a gas connected?
Increasing temp increases pressure which can change volume
