Particles of matter

Question 1

1. What is meant by the term density?

2. What is the equation for density?

Answer 1

1. Density is the amount of matter in a volume

2. m/V

Question 2

Label the arrows that represent the different changes in state

Answer 2

evaporation 
condensation
freezing
melting
deposition
sublimation

Question 3

1. What happens to the mass during a change in state?

2. What is a physical change?

Answer 3

1. Mass is conserved

2. Material can recover original properties if the change is reversed

Question 4

1. What is meant by the term internal energy?

2. What effect does heating have on a system?

Answer 4

1.Total kinetic and potential energy of all particles
2.Kinetic energy increases
Internal energy increases
Particles move more
Temperature increases or there is a change in state

Question 5

1. What is gas pressure?
2. If a gas is held at a constant volume how would you change its pressure?
3. Explain why heating a gas increases its pressure?
4. Explain why cooling a gas decrease its pressure?

Answer 5

1.Gas pressure is force exerted by particles in a gas in a given area
2.Changing the temperature
3.Kinetic energy increases
Internal energy increases
Particles move more
Particles hit the surface more
Pressure increases
4.Kinetic energy decreases
Internal energy decreases
Particles slow down
Less particles hit the surface
Pressure decreases