Temperature and thermodynamics

Question 1

Thermal equilibrium?

Answer 1

Regions of equal temperature

Question 2

Thermal energy?

Answer 2

Energy transferred from one object to another becaue of a temperature difference

Question 3

How is temperature measured?

Answer 3

With physical properties

Question 4

Examples of physical properties used to measure temperature

4

Answer 4

1. density of a liquid- thermometer
2. Volume of a gas at constant pressure, V∝t
3. Resistance of a metal
4. e.m.f of a thermouple

Question 5

Thermodynamic temperature?

talk about scale

Answer 5

Uses a scale that is independant of the physical properties of any particular substance

Question 6

Units of thermodynamic temperature

Answer 6

Kelvin

Question 7

Fixed points of thermodynamic temperature scale

Answer 7

Absolute zero and triple point of pure water

Question 8

What is absolute zero

Answer 8

Temperature at which no more energy can be removed from any body

zero ke and minimal pe

Question 9

conversion from Celcius to Kelvin

Answer 9

+273.15

Question 10

Specific heat capacity definition

Answer 10

The amount of energy required to increase the temperature of a 1kg mass of an object by 1K

Question 11

Specific heat capacity formula

Answer 11

E= mcΔt

Question 12

Specific latent heat def

Answer 12

Thermal energy required to change the state of 1kg of mass of an object without a change in temperature

Question 13

Specific latent heat of fusion/ vaporisation

Answer 13

Fusion:
Thermal energy required to change the state from solid to liquid of 1kg of mass of an object without a change in temperature

Vaporisation:
Thermal energy required to change the state from liquid to gass of 1kg of mass of an object without a change in temperature

Question 14

Specific latent heat formula

Answer 14

L= Q/m

Q=Lm

Question 15

Internal energy def

Answer 15

This is the sum of random distribution of kinetic and potential energies associated with the molecules of a system

Question 16

Internal energy can be determined by?

Answer 16

the state of a system

Question 17

Kinetic energy determines what physical property

Answer 17

Temp

Question 18

Potential energy determines what physical property

Answer 18

state

Question 19

Formula for work done when volume of a gas changes

Answer 19

W=PΔV

Question 20

-W?

Answer 20

Work is done by the gas, gas is expanding

Question 21

+W?

Answer 21

Work is done on the gas, gas is being compressed

Question 22

Requirement for thermal equilibrium

Answer 22

• two regions must be in contact

Question 23

First law of thermodynamics?

Answer 23

U = Q+W

explains that energy is conserved

Question 24

U is?

Answer 24

increase in internal energy

Question 25

Q is?

Answer 25

Energy supplied by heating

Question 26

W is?

Answer 26

Energy supplied doing work

Question 27

Using the simple kinetic model of matter, describe the structure of a solid | 3 points

Answer 27

- particles are very close together - regular, repeating pattern - vibrate about a fixed point

Question 28

# By reference to intermolecular forces explain why the change in internal energy of an ideal gas is equal to the change in total kinetic energy of its molecules. | 2 marks

Answer 28

- in ideal gas, no intermolecular forces - no potential energy