Thermodynamics

Question 1

What is an isolated system?

Answer 1

No heat or matter is transferred

Question 2

What is a closed system?

Answer 2

Where there is an exchange of heat energy

Question 3

What is a open system?

Answer 3

When there is an exchange of both heat energy and matter

Question 4

First law of thermodynamics

Answer 4

Change in Internal Energy = Energy transferred to system - Work Done by System

Question 5

What equation is used for Non-Flow Processes?

Answer 5

PV = NKT

Question 6

What is the 1st Law of Thermodynamics for a isothermal process?

Answer 6

Q = W

Question 7

What is the equation for the change in internal energy for a non-flow process?

Answer 7

Change in internal energy = Q - PChangeinVol

Question 8

Change in internal energy for an isochoric process

Answer 8

Change in internal energy = Q

Question 9

What is the change in internal energy for an adiabatic process?

Answer 9

-W

Question 10

What is the Molar Heat Capacity?

Answer 10

The heat energy required to raise the temperature of 1mol of an ideal gas to be raised by 1K

Question 11

What is the Molar Heat Capacity equation for an isochoric equation?

Answer 11

Change in Internal Energy = nCvChangeinTemo

Question 12

What is the Molar Heat Capacity equation for an isobaric equation?

Answer 12

Change in Internal Energy = nCpChange in temp - pChangeinVol

Question 13

What is Enthalpy(H)

Answer 13

It is the heat energy transferred in a process at constant pressure

Question 14

What is the Enthalpy equation?

Answer 14

Change in H = Change in internal energy + pchangeinV

Question 15

How to use a PV graph to find work?

Answer 15

The work is the area under the PV diagram

Question 16

How to identify an isotherm?

Answer 16

The value of PV is always constant

Question 17

What difference is there between an isotherm and adiabatic curve?

Answer 17

An adiabatic curve is steeper than a isotherm curve

Question 18

How to identify an isochoric process?

Answer 18

An isochoric is a straight vertical line on a PV graph

Question 19

How to identify an isobaric process?

Answer 19

A straight horizontal line on a PV graph

Question 20

How to calculate the net Work Done in a cyclic process?

Answer 20

Area enclosed within the loop

Question 21

Process of 4-stroke Petrol Engine?

Answer 21

Induction, Compression, Expansion and Exhaust

Question 22

What is the Second Law of Thermodynamics?

Answer 22

The entropy of a closed system always increase

Question 23

What is Entropy?

Answer 23

A measure of disorder in a system
Given time a system will always tend towards disorder
Happens spontaneously and does not need energy

Question 24

How does heat flow work in a source?

Answer 24

A heat source will always flow towards a heat sink
Thermal equilibrium is the state of highest entropy

Question 25

How does the heat engine process work?

Answer 25

Source at Temperature Th provides heat energy Qh Heat allows process to occur which does Work Sink at Temperature Tc absorbs heat energy Qc

Question 26

How to find efficiency of heat engine process?

Answer 26

Qh -Qc / Qh

Question 27

How to find theoretical maximum efficiency?

Answer 27

Th - Tc / Th

Question 28

What is the Coefficient of Performance?

Answer 28

A measure of how much heat energy is transferred for the work done

Question 29

What is the CoP for a refrigerator or air conditioner?

Answer 29

Qc / Qh - Qc or Tc / Th - Tc

Question 30

What is the CoP for a heat pump?

Answer 30

Qh/Qh-Qc or Th/Th-Tc