p1.2-Changes of State

Question 1

p1.2.1-What is density?

Answer 1

Density is how much mass there is in a certain volume. It is a property of the material, not the object.

Question 2

p1.2.1-How do you calculate density?

Answer 2

density(kg/m3)= mass(kg)/volume(m3)

Question 3

p1.2.1-What are the properties of the states of matter?

Answer 3

Solid-Very compact and no movement
Liquid-Next to each other, but intermolecular forces are weaker and they can flow.
Gas-Far apart with random motions and a lot of movement.

Question 4

p1.2.1-Why do substances in different states have different densities?

Answer 4

They have a different distance to particles in each state and a different mass.

Question 5

p1.2.2-What is temperature?

Answer 5

Temperature is the measure of the average kinetic energy of particles in a substance and a higher temperature means a higher heat energy. It is measured in degree Celsius or Kelvin.

Question 6

p1.2.2-What is the difference between Energy and Temperature?

Answer 6

Energy is measured in Joules(J)and depends on the arrangement of particles and how fast they are moving or vibrating.
Temperature is the average kinetic energy of the particles and measured in degrees Celsius.

Question 7

p1.2.2-What is internal energy?

Answer 7

The sum of kinetic and potential energy of a substance. Heat energy is in every substance, even if there is low amounts of it.

Question 8

p1.2.2-What can happen after an object is heated?

Answer 8

Heating can change the energy stored within a system to increase the temperature, produce a change of state and make chemical reactions happen.

Question 9

p1.2.2-What is a Physical Change?

Answer 9

A physical change is a change of state and dissolving a substance in another. You do not make new substances and physical changes are easy to reverse as particles are simply rearranged.

Question 10

p1.2.2-What is a Chemical Change?

Answer 10

A chemical change involves joining atoms together in different ways. New substances are produced and there are different particles before and after making it difficult to reverse.

Question 11

p1.2.2-What is the difference between a Physical and Chemical change?

Answer 11

Physical Change-No new substance, particles rearranged, easy to reverse
Chemical Change-New substance, particles completely different, difficult to reverse

Question 12

p1.2.2-What happens if you place a hot object in contact with a cold object?

Answer 12

A hotter object has particles with higher internal energy.
Particles move fast and collide with each other.
They collide with the particles of the cold object and transfer kinetic energy.
The particles of the cold object will start moving faster producing a rise in temperature.

Question 13

p1.2.3-What is Specific Heat Capacity?

Answer 13

Specific Heat Capacity is the heat energy required to raise the temperature of 1Kg of a substance by 1 Kelvin.

Question 14

p1.2.3-What is Internal Energy related to?

Answer 14

Heating increases Internal energy which is the energy related to motion, vibration, rotation and arrangement of particles.

Question 15

p1.2.3-How do you calculate change with Specific Heat Capacity?

Answer 15

Change in Thermal Energy( J ) = mass(kg) x specific heat capacity(J/kg) x change in temperature(C)

Question 16

p1.2.3-Which type of object will have a higher specific heat capacity?

Answer 16

Specific Heat Capacity tells you how resistant a material is to change in temperature and an object with higher Specific Heat Capacity is one which requires more energy to change.

Question 17

P1.2.4-What happens when you heat or cool a substance?

Answer 17

A change of state.

Question 18

p1.2.4-What are all the changes of state?

Answer 18

Solid to Liquid-Melting
Solid to Gas-Sublimation
Liquid to Solid-Freezing
Liquid to Gas-Evaporation/Vaporising
Gas to Solid-Deposition
Gas to Liquid-Condensation

Question 19

p1.2.4-What is Specific Latent Heat?

Answer 19

Specific Latent Heat is the energy transferred when 1kg of a substance changes from one state of matter to another.

Question 20

p1.2.4-How do you calculate with Specific Latent Heat?

Answer 20

thermal energy for
a change of state( J ) =mass(kg) x specific latent heat(J/kg)

Question 21

p1.2.4-How is Specific Latent Heat different from Specific Heat Capacity?

Answer 21

Specific Latent Heat involves energy change of 1kg of a substance for change of state.
Specific Heat Capacity involves energy change of 1kg of a substance for change of temperature.

Question 22

p1.2.4-What 2 types of energy do particles have?

Answer 22

Kinetic Energy-Energy due to motion of the particles. Kinetic Energy is calculated using specific heat capacity and changes if temperature change occurs during heating/cooling.

Potential Energy-Energy due to position of the particles. Potential energy is calculated using specific latent heat and changes if a state change occurs during heating/cooling.