thermal properties of matter

Question 1

internal kinetic energy

Answer 1

due to vibration or movement of particles

lead to rise in temperature

Question 2

internal potential energy

Answer 2

due to the stretching and compressing of interatomic or intermolecular bonds
lead to a change in state

Question 3

heat capacity

Answer 3

amt of thermal energy required to raise the temperature of one substance by 1K or 1 degree
C=Q(thermal energy in J)/change in temp
depends on its mass/material

Question 4

specific heat capacity

Answer 4

amt of thermal energy required to raise the temperature of a unit mass of substance by 1K or 1 degree
c=Q/m(kg)change in temp

Question 5

melting/boiling

why dosent the temp increase

Answer 5

thermal energy absorbed is converted into internal potential energy to overcome the intermolecular bonds so there is no change in internal KE, so temp remain constant

Question 6

freezing/condensation

temp remain constant

Answer 6

only internal potential energy is converted into thermal energy to form intermolecular bonds, no change in IKE, temp remain constant

Question 7

evaporation

Answer 7

surface of liquid, below bp,
the molecules at the surface of liquid gain energy from the surroundings, have enuf KE to overcome the attractive forces of other liquid molecules and force exerted by the atm pressure

Question 8

evaporation causes cooling

Answer 8

water molecules with grter KE escape, leaving molecules with lower KE, results in decrease in temp

Question 9

factors tht affect rate of eva (6)

Answer 9

surface area - larger, faster 
temp- higher, faster 
movement of air- moving, faster 
bp- lower, faster
humidity- more humid, decreases 
pressure- reduce atm pressure, increases

Question 10

(specific) latent heat

Answer 10

amt of thermal energy required to allw (1kg of) a substance to undergo a change in state, wo a change in its temperature
SI unit - J

Question 11

(specific) latent heat of fusion

Answer 11

amt of thermal energy required to change (a unit mass of) a substance frm solid state to liquid state or liquid state to solid state wo a change in temp
Lf(latent heat of fusion)=lf(specific)x m(kg)

Question 12

(specific) latent heat of vaporisation

Answer 12

amt of thermal energy required to change (a unit mass of) a substance from liquid state to gaseous state or gaseous state to liquid state, wo a change in temp
Lv(latent heat of v)=lv(specific) x m(kg)