Description Of Physical Changes Of State

Question 1

Solids particle model

Answer 1

Very close together
Regular arrangement
Held tightly together by strong bonds
Vibrate around a fixed position

Question 2

Liquids particle model

Answer 2

Fairly close together
Bonds between particles are weaker than bonds in solids
Vibrate, can move about and slide past each other

Question 3

Gas particle model

Answer 3

Particles in gas are far apart and spread out
Have no bonds
Move rapidly in all directions and can often collide with each other

Question 4

Liquid -> gas

Answer 4

Particles start in irregular arrangement. Particles mostly touching and can flow over each other. There are weak forces of attraction between particles.
When heat energy is supplied the particles gain energy + start vibrating + moving more and more. Forces of attraction between particles starts to weaken and eventually break
Particles have much more energy, their forces have been broken and they move freely in no fixed arrangement. The particles move very fast with lots of energy. There are no forces of attraction between particles.

Question 5

Liquid -> solid

Answer 5

Particles start in an irregular arrangement. Particles mostly touching and can flow over each other. There are weak forces of attraction between particles.
Particles lose kinetic energy and start moving less and slower when the temperature decreases. The forces of attraction are stronger, so the particles become more compact in arrangement, and are only able to vibrate in a fixed position.Their arrangement becomes regular and fixed also.