Thermodynamics

Question 1

Thermal energy

Answer 1

the sum of translational, rotational and vibrational energy of particles

Question 2

Temperature

Answer 2

Quantity that describes the state of a body related to it’s thermal energy. Can be the graduation or degree of thermal energy.

Question 3

Kelvin

Answer 3

Scientific and absolute temperature scale

Zero point is absolute zero, below which temperature value does not exist. (Particles would stop moving)

0K is the same as -273 degrees celsius

Question 4

Heat

Answer 4

amount of thermal energy transferred between two bodies in thermal interaction.

Unit: Joule (J)

Question 5

How many Joule is 1 cal?

Answer 5

4,186J

Question 6

Heat capacity

Answer 6

Amount of heat needed that needs to be transferred to increase the temperature by one unit.

C= Q/ΔT Unit: J/K

Question 7

Does every heat transfer lead to a temperature change?

Answer 7

NO

We need to transfer heat in order to melt ice, but the temperature will stay 0 degrees celsius

Question 8

Specific heat capacity

Answer 8

c= C/m

Unit: J/(kg*K)

Gives the amount of heat that needs to be transferred to a body of 1 kg mass in order to increase it’s temperature by 1 K. Depends on material.

Question 9

Combination of specific heat capacity and heat capacity

Answer 9

Q= cmΔT

Question 10

Thermal expansion

Answer 10

most bodies expand when getting hotter

BUT!!

water shrinks when heated from 0 to 4 celsius- water is most dense at 4 degrees celsius

Question 11

States of matter

Answer 11

solid: defined volume and shape
liquid: defined volume, no shape
gas: nothing defined.

Question 12

From liquid to gas

Answer 12

boiling

Question 13

From gas to liquid

Answer 13

condensation

Question 14

From solid to gas

Answer 14

sublimation

Question 15

From gas to solid

Answer 15

condensation

Question 16

From solid to liquid

Answer 16

melting

Question 17

From liquid to solid

Answer 17

freezing

Question 18

What happens during phase transition?

Answer 18

Bonds between particles of the body may break up or reform

Question 19

Specific latent heat

Answer 19

L= Q/m

L gives the amount of heat that needs to be transferred in order to transform 1 kg of a material from one phase to another one.

Question 20

Amount of substance

Answer 20

N=v*Na

where v is the amount of substance.

Question 21

Ideal gas

Answer 21

• no interactions (only elastic)
• point like particles
• translational motion

does not exist in reality

Question 22

Ideal gas law

Answer 22

pV = vRT

R=8,314 J/(mol*K)

or

pV=nkBT

kB= Boltzmanns constant

Question 23

Isobaric

Answer 23

Constant pressure

Question 24

Isochoric

Answer 24

Constant volume

Question 25

Isothermal

Answer 25

Constant temperature

Question 26

(PP) How much energy is required to turn 100g of 0 degree celsius ice into 25 degrees celsius of water?
A) 438,9 kJ
B) 338,58 kJ
C)43890 J
D) 43,89 J

Answer 26

C but whyyyyyy????

Question 27

(PP)One mole of ideal gas expands in an isobaric process. Select the correct statement. 
A) The pressure of the gas increases
B)The temperature of the gas decreases
C) The temperature of the gas increases
D) The pressure of the gas decreases

Answer 27

C