Particles Year 9 Flashcards
What is condensation?
When a gas changes into a liquid
What is melting?
When a solid changes into a liquid
What is freezing?
When a liquid changes into a solid
What is evaporation?
When a liquid changes into a gas
What is sublimation?
When a solid changes into a gas
What is deposition?
When a gas changes into a solid v vv
Describe the features of the solid particle
Tightly packed, fixed shape, particles vibrate in place, particles have strong forces between them that keep them in place
Describe the features of the liquid particle
Particles close together, no fixed shape, particles move around each other, particles have moderate forces between them
Describe the features of the gas particle
Particles are far apart, particles move free and quickly, particles have very weak forces between them
What does adding heat to particles do to the particles?
They gain kinetic energy and therefore move faster
What is a physical change?
When a substance changes form but its particles stay the same e.g. melting
What happens during a physical change?
The arrangement and bonds between the particles change but no new substances are formed
What is a chemical change?
When particles change to form new substances
What happens during a chemical change?
The bonds between particles change and new bonds form, new particles are created; this change is irreversible e.g. burning
Name the limitations of the particle model
It doesn’t show the forces between the particles accurately and presents the forces in the model as invisible
It doesn’t show how much energy the particles have
The model assumes all particles are the same size and shape when real particles vary in shape, size and structure
