P3 - Particle Model of Matter

Question 1

What is meant by the term physical changes

Answer 1

When a change can not be reversed

Question 2

What is internal energy

Answer 2

The energy stored in a system by its particles

Question 3

What happens when a system is heated

Answer 3

• internal energy increases.
• causes an increase in temperature or a change of state
• during a change of state the temperature and mass of the substance remains constant

Question 4

What is the name of change of state for gas to liquid

Answer 4

Condensation

Question 5

What is the name of change of state for liquid to gas

Answer 5

Evaporation

Question 6

What is the equation for density

Answer 6

Mass ÷ volume

Question 7

What are the units of density

Answer 7

Kg/m3

Question 8

What happens to the arrangement of water in different states

Answer 8

The less dense, the less compact

Question 9

What are the 2 things that the increase in a systems temperature depend on

Answer 9

Mass and specific heat capacuty (material)

Question 10

Specific latent heat formula

Answer 10

The amount of energy required to heat 1kg of a substance by 1°c without changing the state. Energy = mass latent heat. E=ml

Question 11

What happens when the temperature of a gas increases

Answer 11

• the average energy in the kinetic energy stores of the gas molecules increases.
• average speed of gas molecules increase.
• if the gas is kept at a constant volume, increasing the temperature increases pressure