Master Thermodynamics: Laws, Applications, and Practice Quizzes

Question 1

In the calibration of scientific instruments, how is the Zeroth Law of Thermodynamics applied?

Accepted Answer

To determine that objects in thermal equilibrium have equal temperatures

Answer

To calculate the energy conversion between heat and work

Answer

To predict the direction of spontaneous heat flow

Answer

To measure the entropy of a system

Question 2

Which of the following enunciates the first law of thermodynamics?

Accepted Answer

The overall energy of an isolated system remains constant, barring energy exchange via work or heat.

Answer

Heat cannot spontaneously transfer from a colder object to a hotter object.

Answer

Entropy always increases in an isolated system that has not reached equilibrium.

Answer

Constructing a perpetual motion machine of the first kind is impossible.

Question 3

Which quantity remains constant during an isothermal expansion of an ideal gas?

Accepted Answer

Temperature

Answer

Volume

Answer

Pressure

Answer

Internal energy

Question 4

The efficiency of a Carnot engine is contingent on:

Accepted Answer

Temperatures of both the heat and cold reservoirs

Answer

Solely the temperature of the heat reservoir

Answer

Solely the temperature of the cold reservoir

Answer

The type of working fluid employed

Question 5

Which change in a system leads to a reduction in its internal energy?

Accepted Answer

Extracting heat from the system

Answer

Performing work on the system

Answer

Adding heat to the system

Answer

Compressing the system

Question 6

How does heat transfer influence biological processes like body temperature regulation and enzyme activity?

Accepted Answer

Heat transfer regulates body temperature and affects enzyme efficiency.

Answer

Heat transfer only impacts body temperature, not enzyme activity.

Answer

Heat transfer has no significant impact on biological processes.

Question 7

Which statement is a correct description of the First Law of Thermodynamics?

Accepted Answer

Energy can only be transferred or transformed.

Answer

Energy can be created and destroyed.

Answer

Heat can be converted into work with 100% efficiency.

Answer

The entropy of an isolated system remains constant.

Question 8

What is the mathematical representation of the Second Law of Thermodynamics?

Accepted Answer

dS ≥ 0

Answer

dU = TdS - PdV

Answer

Q = mcΔT

Answer

W = Fd

Question 9

Which application of the Laws of Thermodynamics is used in air conditioning?

Accepted Answer

Rankine cycle

Answer

Carnot cycle

Answer

Otto cycle

Answer

Diesel cycle

Question 10

Which consequence is associated with the Third Law of Thermodynamics?

Accepted Answer

The entropy of a perfect crystal at absolute zero is zero.

Answer

The enthalpy of formation of an element in its standard state is nonzero.

Answer

The Gibbs free energy of a reaction is always positive.

Answer

The equilibrium constant of a reaction is always less than one.

Question 11

What is the relationship between entropy and molecular disorder?

Accepted Answer

Entropy is directly proportional to molecular disorder.

Answer

Entropy is inversely proportional to molecular disorder.

Answer

Entropy is unrelated to molecular disorder.

Answer

Entropy is equal to molecular disorder.

Question 12

Which is NOT a type of thermodynamic system?

Accepted Answer

Semi-closed system

Answer

Open system

Answer

Closed system

Answer

Isolated system

Question 13

What is the significance of Gibbs free energy in biochemical reactions?

Accepted Answer

It determines the spontaneity of biochemical reactions.

Answer

It is a measure of the total energy of a system.

Answer

It is used to calculate the equilibrium constant of a reaction.

Answer

It is independent of temperature and pressure.

Question 14

Which of the following is a correct statement of the first law of thermodynamics?

Accepted Answer

Total energy of an isolated system remains constant.

Answer

Energy can be created or destroyed at will.

Answer

Heat can be transferred spontaneously from a cold object to a hot object.

Answer

Entropy of an isolated system decreases over time.

Question 15

Express the mathematical equation for the second law of thermodynamics.

Accepted Answer

dS ≥ 0

Answer

dU = TdS - PdV

Answer

dG = dH - TdS

Answer

E = mc²

Question 16

Define Gibbs free energy and explain its significance.

Accepted Answer

Gibbs free energy represents the maximum useful work that can be extracted from a system at constant temperature and pressure.

Answer

Gibbs free energy represents the minimum work required to maintain a system in equilibrium.

Answer

Gibbs free energy is equivalent to the total energy of a system.

Answer

Gibbs free energy measures the entropy of a system.

Question 17

According to the third law of thermodynamics, what is the entropy of a pure crystalline substance at absolute zero?

Accepted Answer

Zero

Answer

Positive

Answer

Negative

Answer

Cannot be determined

Question 18

Which equation correctly represents the internal energy of a system?

Accepted Answer

E = q + w

Answer

E = TS - PV

Answer

E = mc²

Answer

G = H - TS

Question 19

According to the Second Law of Thermodynamics, what happens to the total entropy of an isolated system over time?

Accepted Answer

It increases

Answer

It remains constant

Answer

It decreases

Answer

It fluctuates

Question 20

Which equation represents the mathematical expression of the First Law of Thermodynamics?

Accepted Answer

dQ = dU + dW

Answer

dS > 0

Answer

S = 0 at absolute zero

Answer

T = 0 at absolute zero

Question 21

What is the change in entropy of a system during a reversible process?

Accepted Answer

Zero

Answer

Positive

Answer

Negative

Answer

Indeterminate

Question 22

Which of the following processes is NOT spontaneous?

Accepted Answer

Sublimation of dry ice at room temperature

Answer

Melting of ice at room temperature

Answer

Diffusion of gases

Answer

Mixing of salt and water

Question 23

How is the Gibbs free energy (G) of a system related to its entropy (S) and temperature (T)?

Accepted Answer

G = H - TS

Answer

G = U + TS

Answer

G = H + TS

Answer

G = U - TS

Question 24

During an adiabatic process, what happens to the internal energy of a system?

Accepted Answer

It remains constant

Answer

It increases

Answer

It decreases

Answer

It fluctuates

Question 25

Which of the following equations represents the Clausius inequality?

Accepted Answer

dS ≥ dQ/T

Answer

dS ≤ dQ/T

Answer

dS = dQ/T

Answer

dS > dQ/T

Question 26

According to the Zeroth Law of Thermodynamics, which of the following is true?

Accepted Answer

If two systems are in thermal equilibrium with a third system, they are in thermal equilibrium with each other.

Answer

Heat flows from a colder object to a hotter object.

Answer

Thermal equilibrium occurs when two systems have different temperatures.

Answer

The temperature of a system is a measure of its potential energy.

Question 27

According to the second law of thermodynamics, which statement accurately describes entropy changes?

Accepted Answer

The total entropy of a system and its surroundings always increases over time.

Answer

Entropy always decreases in an isolated system.

Answer

The total entropy of the universe always decreases.

Answer

Heat can spontaneously flow from a colder object to a hotter object.

Question 28

Which of the following is a correct statement of the first law of thermodynamics?

Accepted Answer

Energy can be transformed from one form to another, but it cannot be created or destroyed.

Answer

The entropy of an isolated system always increases.

Answer

The temperature of an isolated system always decreases.

Answer

Heat and work can be freely converted.

Question 29

In a spontaneous process, what is the change in entropy of the universe?

Accepted Answer

Increases

Answer

Decreases

Answer

Cannot be determined

Answer

Remains constant

Question 30

What is a consequence of the third law of thermodynamics?

Accepted Answer

The entropy of a perfect crystal at absolute zero is zero.

Answer

The heat capacity of all substances decreases at high temperatures.

Answer

The entropy of all substances is the same at room temperature.

Question 31

Which of the following is an application of the laws of thermodynamics in biology?

Accepted Answer

Predicting the direction of biochemical reactions.

Answer

Developing new materials with high thermal conductivity.

Answer

Designing energy-efficient buildings.

Question 32

Consider a system where 200 J of heat is added and 100 J of work is done on the system. What is the change in internal energy of the system?

Accepted Answer

300 J

Answer

100 J

Answer

200 J

Question 33

Which of the following is the mathematical expression of the third law of thermodynamics?

Accepted Answer

S -> 0 as T -> 0

Answer

dU = TdS - PdV

Answer

W = -PΔV

Answer

G = H - TS

Question 34

In a reversible process, what is true about the entropy of the universe?

Accepted Answer

It remains constant.

Answer

It can either increase or decrease.

Answer

It decreases.

Answer

It increases.

Question 35

What is the SI unit of entropy?

Accepted Answer

Joule per Kelvin

Answer

Watt per square meter

Answer

Pascal per cubic meter

Answer

Calorie per gram

Question 36

Which law of thermodynamics states that energy cannot be created or destroyed, only transferred or transformed?

Accepted Answer

First Law of Thermodynamics

Answer

Third Law of Thermodynamics

Answer

Second Law of Thermodynamics

Answer

Fourth Law of Thermodynamics

Question 37

In an isolated system, the total entropy always:

Accepted Answer

Increases or remains constant

Answer

Decreases

Answer

Alternates between increasing and decreasing

Answer

Stays the same

Question 38

According to the Third Law of Thermodynamics, the entropy of a pure crystalline substance at absolute zero is:

Accepted Answer

Zero

Answer

Positive

Answer

Negative

Answer

Indeterminate

Question 39

Which of the following processes is considered irreversible?

Accepted Answer

Heat dissipation

Answer

Reversible Carnot cycle

Answer

Adiabatic compression

Answer

Isothermal expansion

Question 40

The efficiency of a heat engine is defined as:

Accepted Answer

Work Output / Heat Input

Answer

Temperature Difference / Heat Transfer

Answer

Heat Input / Work Output

Answer

Change in Entropy / Temperature

Question 41

In an adiabatic process:

Accepted Answer

No heat is transferred to or from the system

Answer

Pressure and volume are inversely proportional

Answer

Temperature remains constant

Answer

Entropy increases

Question 42

Diffusion of a gas from a region of high concentration to a region of low concentration is an example of a:

Accepted Answer

Spontaneous process

Answer

Non-spontaneous process

Answer

Equilibrium process

Answer

Reversible process

Question 43

The enthalpy of a reaction is equal to the:

Accepted Answer

Change in internal energy plus the change in (Pressure * Volume)

Answer

Change in internal energy alone

Answer

Change in entropy alone

Question 44

Which of the following factors influences the equilibrium constant of a reaction?

Accepted Answer

Temperature

Answer

Pressure only

Answer

Concentration of reactants only

Answer

Volume only

Question 45

Which statement BEST defines the first law of thermodynamics?

Accepted Answer

Energy cannot be created or destroyed; it can only be transferred or transformed.

Answer

Heat naturally moves from a colder object to a warmer one.

Answer

The entropy of a closed system always increases.

Question 46

A system absorbs 100 Joules (J) of heat and performs 50 J of work. What is the change in internal energy of the system?

Accepted Answer

50 J

Answer

0 J

Answer

-50 J

Answer

150 J

Question 47

The second law of thermodynamics states that:

Accepted Answer

The entropy of an isolated system always increases over time.

Answer

The total energy of a system and its surroundings remains constant.

Answer

Energy cannot be created or destroyed.

Question 48

Living organisms maintain a high level of order and complexity. How does this align with the second law of thermodynamics?

Accepted Answer

Living organisms are open systems that exchange energy and matter with their environment, increasing the entropy of the universe.

Answer

Living organisms do not follow the laws of thermodynamics.

Answer

The entropy of a living organism always decreases.

Question 49

The third law of thermodynamics states that:

Accepted Answer

The entropy of a perfect crystal at absolute zero (0 Kelvin) is zero.

Answer

The entropy of an isolated system always increases.

Answer

Energy cannot be created or destroyed.

Question 50

Which statement BEST describes the concept of Gibbs free energy (ΔG)?

Accepted Answer

The amount of energy available to do useful work during a thermodynamic process at constant temperature and pressure.

Answer

The energy required to break bonds in a chemical reaction.

Answer

The total energy of a system and its surroundings.

Question 51

A reaction with a negative ΔG is considered:

Accepted Answer

Spontaneous

Answer

Non-spontaneous

Answer

At equilibrium

Answer

Endergonic

Question 52

Which factors can influence the spontaneity of a reaction?

Accepted Answer

All of the above

Answer

Enthalpy change (ΔH)

Answer

Entropy change (ΔS)

Answer

Temperature

Question 53

The process of photosynthesis in plants is an example of:

Accepted Answer

An endergonic reaction

Answer

An exergonic reaction

Answer

A spontaneous reaction

Answer

A reaction that does not involve energy transfer.