Particle Model of Matter

Question 1

Why are solids and liquids incompressible

-difference between them

Answer 1

there are no gaps between the particles in them

liquids contain particles that are free to move allowing them to change shape and fit into their container

Question 2

What is internal energy

Answer 2

the total kinetic energy and potential energy of all the particles in a system and is stored by the particles

Question 3

What causes a substance to change state at the melting and boiling point
what is a change of state

Answer 3

the energy being added not the temperature

a change of state alters the internal energy but not the temperature or mass - not a chemical change

Question 4

what is the latent heat of fusion

Answer 4

the energy needed for a substance to change from a solid to a liquid (melt)

Question 5

what is latent heat of vaporisation

Answer 5

the energy needed for a substance to change from a liquid to a gas (evaporate)

Question 6

what does the horizontal part on a heating / cooling graph indicate

Answer 6

where energy is being used to change state