P3 - Particle Model of Matter

Question 1

In which state of matter do particles move fastest?

Answer 1

Gas

Question 2

In which state of matter is density generally highest? How is this explained by the particle model?

Answer 2

Solid. In the particle model, particles are arranged closest together in the solid state.

Question 3

What does density tell you about a substance?

Answer 3

How compact the substance is, or how much mass there is per unit of volume.

Question 4

What’s the equation used for calculating density?

Answer 4

Density = mass / volume

or p = m / V

Question 5

Name an appropriate piece of equipment for measuring the thickness of a penny.

Answer 5

Vernier callipers or a micrometer

Question 6

During which two changes of state does liquid become a gas?

Answer 6

Boiling and evaporation

Question 7

What is sublimation?

Answer 7

The physical change of a substance from a solid state to a gas state without passing through a liquid state.

Question 8

True or false? The internal energy of a system is equal to the total energy that all the particles of the system have in their kinetic energy stores.

Answer 8

False. It’s the total energy in the kinetic and potential energy stores of all the particles.

Question 9

What is the specific latent heat of vaporisation of a substance?

Answer 9

The energy needed to change 1kg of the substance from a liquid into a vapour/gas without raising the temperature of the substance.

Question 10

What happens to the internal energy of a substance when it is condensing?

Answer 10

Decreases. This is because bonds are forming which releases energy.