Thermodynamic Property Tables and Charts: Master the Basics for Engineering Success

Question 1

What is the primary purpose of using a saturation table?

Accepted Answer

To obtain properties of a substance in the liquid-vapour coexistence region

Answer

To determine the properties of a substance at a specified pressure

Answer

To calculate the work output of a thermodynamic process

Answer

To visualize the phase behaviour of a substance

Question 2

Which interpolation method is most commonly employed for thermodynamic property interpolation?

Accepted Answer

Linear interpolation

Answer

Parabolic interpolation

Answer

Cubic interpolation

Answer

Logarithmic interpolation

Question 3

Which property can be directly obtained from a P-h diagram?

Accepted Answer

Enthalpy

Answer

Specific heat capacity

Answer

Entropy

Answer

Volume

Question 4

On a temperature-entropy diagram, what is the significance of the critical point?

Accepted Answer

It represents the highest pressure and temperature at which liquid and vapor can coexist in equilibrium.

Answer

It marks the boundary between the liquid and gas phases.

Answer

It indicates the state at which the specific heat capacity of a substance is maximum.

Answer

It is the point at which the substance has zero entropy.

Question 5

On a pressure-enthalpy diagram, what is the difference between an isobar and an isotherm?

Accepted Answer

An isobar is a constant pressure line, while an isotherm is a constant temperature line.

Answer

An isotherm is a constant pressure line, while an isobar is a constant temperature line.

Answer

Isobars and isotherms are the same.

Answer

An isobar is a line of constant specific volume, while an isotherm is a line of constant specific enthalpy.

Question 6

Which of the following is a fundamental assumption made in the development of thermodynamic property tables?

Accepted Answer

The substance is in a state of thermodynamic equilibrium.

Answer

The substance behaves as an ideal gas.

Answer

The substance is incompressible.

Answer

The substance has constant specific heat capacity.

Question 7

What is the difference between enthalpy and internal energy?

Accepted Answer

Enthalpy is the sum of internal energy and pressure-volume work, while internal energy is the energy stored within the system.

Answer

Internal energy is the sum of internal energy and pressure-volume work, while enthalpy is the energy stored within the system.

Answer

Enthalpy and internal energy are the same.

Answer

Enthalpy is the energy transferred into the system as heat, while internal energy is the energy transferred into the system as work.

Question 8

Which of the following is NOT a type of thermodynamic property table?

Accepted Answer

Chemical tables

Answer

Steam tables

Answer

Refrigerant tables

Answer

Psychrometric charts

Question 9

Which of the following is NOT a type of thermodynamic property table?

Accepted Answer

Chemical kinetics tables

Answer

Steam tables

Answer

Refrigerant tables

Answer

Combustion tables

Question 10

What does the saturation line in a pressure-enthalpy diagram indicate?

Accepted Answer

Phase change boundary

Answer

Critical point

Answer

Relationship between pressure and temperature

Answer

Specific heat capacity

Question 11

How is absolute pressure different from relative pressure?

Accepted Answer

Absolute pressure includes atmospheric pressure, while relative pressure does not

Answer

Relative pressure includes atmospheric pressure, while absolute pressure does not

Answer

Absolute and relative pressures are measured from different datums

Answer

There is no difference between absolute and relative pressure

Question 12

Which of the following is NOT a state property?

Accepted Answer

Work

Answer

Temperature

Answer

Entropy

Answer

Specific volume

Question 13

What is the definition of reduced pressure?

Accepted Answer

Actual pressure divided by the critical pressure

Answer

Actual temperature divided by the critical temperature

Answer

Critical pressure divided by the actual pressure

Answer

Critical temperature divided by the actual temperature

Question 14

What is the definition of specific heat capacity at constant volume?

Accepted Answer

Heat required to raise the temperature of a unit mass by one kelvin at constant volume

Answer

Heat required to raise the temperature of a unit mass by one kelvin at constant pressure

Answer

Work done by a unit mass when its volume changes by one cubic meter at constant temperature

Answer

Work done on a unit mass when its pressure changes by one pascal at constant volume

Question 15

What is the enthalpy of vaporization?

Accepted Answer

Heat required to convert a unit mass of a liquid to a gas at its boiling point

Answer

Heat required to convert a unit mass of a gas to a liquid at its boiling point

Answer

Heat required to raise the temperature of a unit mass by one kelvin at its boiling point

Answer

Heat required to lower the temperature of a unit mass by one kelvin at its boiling point

Question 16

How do ideal gases differ from real gases?

Accepted Answer

Ideal gases obey the ideal gas law, while real gases deviate from it

Answer

Real gases obey the ideal gas law, while ideal gases deviate from it

Answer

Ideal gases have constant specific heats, while real gases do not

Answer

Real gases have constant specific heats, while ideal gases do not

Question 17

Which of the following is NOT a characteristic of a thermodynamic property?

Accepted Answer

It is dependent on the mass of the system.

Answer

It is a state function.

Answer

It is measurable.

Answer

It is independent of the path taken to reach a state.

Question 18

What is the primary distinction between a thermodynamic table and a thermodynamic chart?

Accepted Answer

Tables provide data at specific states, while charts provide data over a range of states.

Answer

Charts provide data at specific states, while tables provide data over a range of states.

Answer

Tables are more accurate than charts.

Answer

Charts are only applicable to pure substances, whereas tables can be applied to mixtures.

Question 19

What is the process of estimating data between tabulated values in a thermodynamic table called?

Accepted Answer

Interpolation

Answer

Extrapolation

Answer

Linear regression

Answer

Numerical integration

Question 20

Which of the following is NOT a common application of thermodynamic property tables?

Accepted Answer

Predicting weather patterns

Answer

Designing heat exchangers

Answer

Analyzing power cycles

Answer

Calculating fluid flow rates

Question 21

What is the primary purpose of using a Mollier chart?

Accepted Answer

To visualize the changes in enthalpy and entropy for a given process.

Answer

To determine the properties of a substance at a given state.

Answer

To calculate the efficiency of a heat engine.

Answer

To design refrigeration systems.

Question 22

Identify the option that does not represent a type of thermodynamic property table.

Accepted Answer

Enthalpy-entropy diagrams

Answer

Steam tables

Answer

Refrigerant tables

Answer

Psychometric charts

Question 23

What is the significance of the triple point on a phase diagram?

Accepted Answer

It indicates the temperature and pressure at which a solid, liquid, and gas are in equilibrium

Answer

It represents the state where all three phases of a substance coexist

Answer

It marks the boundary between the solid and liquid phases

Answer

It signifies the critical point of a substance

Question 24

During an isothermal process, which thermodynamic property remains constant?

Accepted Answer

Temperature

Answer

Pressure

Answer

Volume

Answer

Entropy

Question 25

Describe the fundamental distinction between intensive and extensive properties.

Accepted Answer

An extensive property depends on the amount of matter while an intensive property does not

Answer

An intensive property depends on the amount of matter while an extensive property does not

Answer

Both intensive and extensive properties depend on the amount of matter

Answer

Neither intensive nor extensive properties depend on the amount of matter

Question 26

Identify an example of an irreversible process.

Accepted Answer

Mixing two gases at constant temperature

Answer

Adiabatic expansion of an ideal gas

Answer

Isothermal compression of a gas

Answer

Heat transfer through a well-insulated wall

Question 27

Provide a concise definition of entropy.

Accepted Answer

A measure of the randomness or disorder of a system

Answer

A measure of the energy of a system

Answer

A measure of the volume of a system

Answer

A measure of the temperature of a system

Question 28

**What is the significance of the critical point on a pressure-temperature phase diagram?**

Accepted Answer

Disappearance of the distinction between liquid and gas phases

Answer

Irreversible change of state

Answer

Maximum density of the substance

Question 29

Which thermodynamic property table is specifically designed for gases at low pressures?

Accepted Answer

Ideal Gas Table

Answer

Steam Table

Answer

Refrigerant Table

Answer

Liquid Water Table

Question 30

For determining the dew point temperature of a moist air mixture, which tool is most appropriate?

Accepted Answer

Psychrometric Chart

Answer

Phase Diagram

Answer

Mollier Diagram

Answer

Enthalpy-Entropy Chart

Question 31

On an Enthalpy-Entropy Chart, which property is displayed on the y-axis?

Accepted Answer

Entropy

Answer

Temperature

Answer

Enthalpy

Answer

Pressure

Question 32

What is the significance of the triple point on a Phase Diagram?

Accepted Answer

Indicates the coexistence of three phases at equilibrium

Answer

Represents the critical point of the substance

Answer

Shows the melting point of the substance

Question 33

Which factor does NOT affect the accuracy of property data obtained from tables and charts?

Accepted Answer

User interpretation

Answer

Precision of measuring instruments

Answer

Interpolation method

Answer

Experimental error

Question 34

Which of the following is NOT a type of thermodynamic property table?

Accepted Answer

Mass Transfer Data

Answer

Psychrometric Charts

Answer

Steam Tables

Answer

Refrigerant Tables

Question 35

What is the main purpose of a Mollier chart?

Accepted Answer

To represent enthalpy and entropy data

Answer

To represent temperature and pressure data

Answer

To represent volume and entropy data

Answer

To represent pressure and enthalpy data

Question 36

What is a major limitation of using thermodynamic property tables and charts?

Accepted Answer

They may not provide data for all substances

Answer

They are only accurate for ideal gases

Answer

They require specialized software to use

Answer

They are inherently difficult to use

Question 37

Which of the following is an advantage of using a steam table over a refrigerant table?

Accepted Answer

Steam tables generally offer more comprehensive data

Answer

Steam tables are easier to use

Answer

Refrigerant tables are more widely available

Answer

Refrigerant tables are innately more accurate

Question 38

What is the critical point of a substance?

Accepted Answer

The point at which the liquid and vapor phases become indistinguishable

Answer

The point where the substance reaches its highest pressure

Answer

The point where the substance reaches its highest temperature

Question 39

What is the primary purpose of using a thermodynamic property chart?

Accepted Answer

To obtain property data for a substance at a specific state.

Answer

To determine the work and heat transfer in a process.

Answer

To identify the phase of a substance.

Question 40

What is the recommended interpolation method for estimating property values between tabulated values in a thermodynamic property table?

Accepted Answer

Linear Interpolation

Answer

Inverse Distance Weighting

Answer

Cubic Spline Interpolation

Answer

Lagrange Polynomial Interpolation

Question 41

Which of the following substances typically has the highest specific heat capacity?

Accepted Answer

Water

Answer

Air

Answer

Helium

Answer

Iron

Question 42

What is the fundamental difference between enthalpy and internal energy?

Accepted Answer

Enthalpy includes flow work, while internal energy does not.

Answer

Internal energy includes potential energy, while enthalpy does not.

Answer

Enthalpy is a property of an open system, while internal energy is a property of a closed system.

Question 43

Which thermodynamic process is represented by a horizontal line on a temperature-entropy diagram?

Accepted Answer

Isothermal Process

Answer

Isobaric Process

Answer

Isochoric Process

Answer

Adiabatic Process

Question 44

What is the significance of the triple point on a phase diagram?

Accepted Answer

It represents the temperature and pressure at which all three phases of a substance coexist in equilibrium.

Answer

It indicates the critical point of the substance.

Answer

It determines the boiling point of the substance at a given pressure.

Question 45

What is the primary advantage of using a Mollier diagram over other thermodynamic property charts?

Accepted Answer

It allows for direct determination of both enthalpy and entropy changes.

Answer

It provides more accurate property data than other charts.

Answer

It can be used for a wider range of fluids.