Topic 3 - Particle model of matter

Question 1

What is the equation for density?

Answer 1

Density (kg/m^3) = mass (kg) / volume (m^3)

Question 2

What are the three states of matter and explain each?

Answer 2

• – Solids: tightly packed so highest density, strong force of attraction, fixed and regular arrangement
• – Liquids: weaker force of attraction, particles move past each other, close together, irregular arrangement
• – Gases: weakest force of attraction, most energy, move freely in random directions at high speeds

Question 3

What are the different changes of state?

Answer 3

• – Solid to liquid: melting
• – Liquid to gas: boiling / evaporating
• – Gas to liquid: condensation
• – Liquid to solid: freezing
• – Solid to gas: sublimation

Question 4

What is internal energy?

Answer 4

Internal energy is the total kinetic energy and potential energy of all particles in a system.

Question 5

What is specific heat capacity? What is the equation for specific heat capacity?

Answer 5

— Specific heat capacity is the amount of energy needed to heat 1kg of a substance by one degrees celsius.

change in thermal energy = massspecific heat capacitychange in temperature

Question 6

What is specifc latent heat? What is the equation?

Answer 6

— Specifc latent heat is the amount of energy required to change the state of 1kg of a substance without changing the temperature.

Energy = mass*specific latent heat