__________ decreases during adiabatic throttling of a perfect gas. (A) Entropy (B) Temperature (C) Enthalpy (D) Pressure

__________ decreases during adiabatic throttling of a perfect gas. (A) Entropy
(B) Temperature
(C) Enthalpy
(D) Pressure
by

1 Answer

Answer :

(D) Pressure
by

Related questions

The adiabatic throttling process of a perfect gas is one of constant enthalpy (A) In which there is a temperature drop (B) Which is exemplified by a non-steady flow expansion (C) Which can be performed in a pipe with a constriction (D) In which there is an increase in temperature

Description : The adiabatic throttling process of a perfect gas is one of constant enthalpy (A) In which there is a temperature drop (B) Which is exemplified by a non-steady flow expansion (C) Which can be performed in a pipe with a constriction (D) In which there is an increase in temperature

Last Answer : (C) Which can be performed in a pipe with a constriction

Throttling (Joule-Thomson effect) process is a constant __________ process. (A) Enthalpy (B) Entropy (C) Pressure (D) None of these

Description : Throttling (Joule-Thomson effect) process is a constant __________ process. (A) Enthalpy (B) Entropy (C) Pressure (D) None of these

Last Answer : (A) Enthalpy

Joule-Thomson effect i.e., a throttling process is a constant __________ process. (A) Entropy (B) Temperature (C) Internal energy (D) Enthalpy

Description : Joule-Thomson effect i.e., a throttling process is a constant __________ process. (A) Entropy (B) Temperature (C) Internal energy (D) Enthalpy

Last Answer : (D) Enthalpy

Throttling process is a/an __________ process. (A) Reversible and isothermal (B) Irreversible and constant enthalpy (C) Reversible and constant entropy (D) Reversible and constant enthalpy

Description : Throttling process is a/an __________ process. (A) Reversible and isothermal (B) Irreversible and constant enthalpy (C) Reversible and constant entropy (D) Reversible and constant enthalpy

Last Answer : (B) Irreversible and constant enthalpy

An adiabatic process in which there is no change in system enthalpy but for which there is a significant decrease in pressure is called _____.  A. Isochoric process  B. Isobaric process  C. Throttling process  D. Quasistatic process

Description : An adiabatic process in which there is no change in system enthalpy but for which there is a significant decrease in pressure is called _____.  A. Isochoric process  B. Isobaric process  C. Throttling process  D. Quasistatic process

Last Answer : Throttling process

Joule-Thomson co-efficient is the ratio of (A) Pressure change to temperature change occuring during adiabatic compression of a gas (B) Pressure change to temperature change occuring during adiabatic throttling of a gas (C) Temperature change to pressure change occuring during adiabatic compression of a gas (D) Temperature change to pressure change occuring during adiabatic throttling of a gas

Description : Joule-Thomson co-efficient is the ratio of (A) Pressure change to temperature change occuring during adiabatic compression of a gas (B) Pressure change to temperature change occuring during adiabatic ... a gas (D) Temperature change to pressure change occuring during adiabatic throttling of a gas

Last Answer : (D) Temperature change to pressure change occuring during adiabatic throttling of a gas

During throttling process  (a) heat exchange does not take place  (b) no work is done by expanding steam  (c) there is no change of internal energy of steam  (d) all of the above  (e) entropy decreases.

Description : During throttling process  (a) heat exchange does not take place  (b) no work is done by expanding steam  (c) there is no change of internal energy of steam  (d) all of the above  (e) entropy decreases.

Last Answer : Answer : d

Specific __________ does not change during phase change at constant temperature and pressure. (A) Entropy (B) Gibbs energy (C) Internal energy (D) Enthalpy

Description : Specific __________ does not change during phase change at constant temperature and pressure. (A) Entropy (B) Gibbs energy (C) Internal energy (D) Enthalpy

Last Answer : (B) Gibbs energy

For an incompressible fluid, the __________ is a function of both pressure as well as temperature. (A) Internal energy (B) Enthalpy (C) Entropy (D) All (A), (B) & (C)

Description : For an incompressible fluid, the __________ is a function of both pressure as well as temperature. (A) Internal energy (B) Enthalpy (C) Entropy (D) All (A), (B) & (C)

Last Answer : (B) Enthalpy

Mollier chart is a __________ plot. (A) Pressure vs. enthalpy (B) Pressure vs. volume (C) Enthalpy vs. entropy (D) Temperature vs. entropy

Description : Mollier chart is a __________ plot. (A) Pressure vs. enthalpy (B) Pressure vs. volume (C) Enthalpy vs. entropy (D) Temperature vs. entropy

Last Answer : (C) Enthalpy vs. entropy

Enthalpy changes over a constant pressure path are always zero for __________ gas. (A) Any (B) A perfect (C) An easily liquefiable (D) A real

Description : Enthalpy changes over a constant pressure path are always zero for __________ gas. (A) Any (B) A perfect (C) An easily liquefiable (D) A real

Last Answer : (B) A perfect

Which of the following processes are thermodynamically reversible  (a) throttling  (b) free expansion  (c) constant volume and constant pressure  (d) hyperbolic and pV = C  (e) isothermal and adiabatic.

Description : Which of the following processes are thermodynamically reversible  (a) throttling  (b) free expansion  (c) constant volume and constant pressure  (d) hyperbolic and pV = C  (e) isothermal and adiabatic.

Last Answer : Answer : e

A heat exchange process in which the product of pressure and volume remains constant is known as  (a) heat exchange process  (b) throttling process  (c) isentropic process  (d) adiabatic process  (e) hyperbolic process.

Description : A heat exchange process in which the product of pressure and volume remains constant is known as  (a) heat exchange process  (b) throttling process  (c) isentropic process  (d) adiabatic process  (e) hyperbolic process.

Last Answer : Answer : e

If a gas vapour is allowed to expand through a very minute aperture, then such a process is known as  (a) free expansion  (b) hyperbolic expansion  (c) adiabatic expansion  (d) parabolic expansion  (e) throttling.

Description : If a gas vapour is allowed to expand through a very minute aperture, then such a process is known as  (a) free expansion  (b) hyperbolic expansion  (c) adiabatic expansion  (d) parabolic expansion  (e) throttling.

Last Answer : Answer : e

Isentropic process means a constant __________ process. (A) Enthalpy (B) Pressure (C) Entropy (D) None of these

Description : Isentropic process means a constant __________ process. (A) Enthalpy (B) Pressure (C) Entropy (D) None of these

Last Answer : (C) Entropy

Pick out the wrong statement: (A) The expansion of a gas in vacuum is an irreversible process (B) An isometric process is a constant pressure process (C) Entropy change for a reversible adiabatic process is zero (D) Free energy change for a spontaneous process is negative

Description : Pick out the wrong statement: (A) The expansion of a gas in vacuum is an irreversible process (B) An isometric process is a constant pressure process (C) Entropy change for a reversible adiabatic process is zero (D) Free energy change for a spontaneous process is negative

Last Answer : (B) An isometric process is a constant pressure process

If a solid is compressed adiabatically in its elastic range, its __________ remains constant (A) Internal energy (B) Enthalpy (C) Entropy (D) Temperature

Description : If a solid is compressed adiabatically in its elastic range, its __________ remains constant (A) Internal energy (B) Enthalpy (C) Entropy (D) Temperature

Last Answer : (C) Entropy

After throttling, gas temperature (A) Decreases (B) Increases (C) Remain same (D) May increase or decrease; depends on the nature of

Description : After throttling, gas temperature (A) Decreases (B) Increases (C) Remain same (D) May increase or decrease; depends on the nature of

Last Answer : (A) Decreases

Entropy of a substance remains constant during a/an __________ change. (A) Reversible isothermal (B) Irreversible isothermal (C) Reversible adiabatic (D) None of these

Description : Entropy of a substance remains constant during a/an __________ change. (A) Reversible isothermal (B) Irreversible isothermal (C) Reversible adiabatic (D) None of these

Last Answer : (C) Reversible adiabatic

Pick out the correct statement. (A) Like internal energy and enthalpy, the absolute value of standard entropy for elementary substances is zero (B) Melting of ice involves increase in enthalpy and a decrease in randomness (C) The internal energy of an ideal gas depends only on its pressure (D) Maximum work is done under reversible conditions

Description : Pick out the correct statement. (A) Like internal energy and enthalpy, the absolute value of standard entropy for elementary substances is zero (B) Melting of ice involves increase in enthalpy and ... of an ideal gas depends only on its pressure (D) Maximum work is done under reversible conditions

Last Answer : (D) Maximum work is done under reversible conditions

Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.). (A) Entropy (B) Internal energy (C) Enthalpy (D) Gibbs free energy

Description : Specific __________ does not change during a phase change (e.g. sublimation, melting, vaporisation etc.). (A) Entropy (B) Internal energy (C) Enthalpy (D) Gibbs free energy

Last Answer : (D) Gibbs free energy

All gases except __________ shows a cooling effect during throttling process at atmospheric temperature and pressure. (A) Oxygen (B) Nitrogen (C) Air (D) Hydrogen

Description : All gases except __________ shows a cooling effect during throttling process at atmospheric temperature and pressure. (A) Oxygen (B) Nitrogen (C) Air (D) Hydrogen

Last Answer : (D) Hydrogen

Assertion :- Entropy of system increases for a spontaneous reactions. Reason :- Enthalpy of reaction always decreases for spontaneous reaction.

Description : Assertion :- Entropy of system increases for a spontaneous reactions. Reason :- Enthalpy of reaction always decreases for spontaneous reaction.

Last Answer : Assertion :- Entropy of system increases for a spontaneous reactions. Reason :- Enthalpy of reaction ... D. If both Assertion & Reason are false.

During Joule-Thomson expansion of gases (A) Enthalpy remains constant (B) Entropy remains constant (C) Temperature remains constant (D) None of these

Description : During Joule-Thomson expansion of gases (A) Enthalpy remains constant (B) Entropy remains constant (C) Temperature remains constant (D) None of these

Last Answer : (A) Enthalpy remains constant

Vertical lines on pressure-enthalpy chart show constant (a) pressure lines (b) temperature lines (c) total heat lines (d) entropy lines

Description : Vertical lines on pressure-enthalpy chart show constant (a) pressure lines (b) temperature lines (c) total heat lines (d) entropy lines

Last Answer : Ans: c

On the pressure-enthalpy diagram, condensation and de-superheating is represented by a horizontal line because theprocess (a) takes place at constant pressure (b) takes place at constant temperature (c) takes place at constant entropy (d) takes place at constant enthalpy

Description : On the pressure-enthalpy diagram, condensation and de-superheating is represented by a horizontal line because theprocess (a) takes place at constant pressure (b) takes place at constant temperature (c) takes place at constant entropy (d) takes place at constant enthalpy

Last Answer : Ans: a

Short horizontal lines on pressure-enthalpy chart show (a) constant pressure lines (b) constant temperature lines (c) constant total heat lines (d) constant entropy lines

Description : Short horizontal lines on pressure-enthalpy chart show (a) constant pressure lines (b) constant temperature lines (c) constant total heat lines (d) constant entropy lines

Last Answer : Ans: a

What are the names given to constant temperature, constant pressure, constant volume, constant internal energy, constant enthalpy, and constant entropy processes.

Description : What are the names given to constant temperature, constant pressure, constant volume, constant internal energy, constant enthalpy, and constant entropy processes.

Last Answer : Isothermal, isochroic, isobaric, free expression, throttling and adiabatic processes respectively.

For a thermodynamic system undergoing a process, which of the following pairs best expresses the relationship similar to that expressed by the pressure volume plot? (A) Temperature - entropy (B) Temperature - pressure (C) Enthalpy - entropy

Description : For a thermodynamic system undergoing a process, which of the following pairs best expresses the relationship similar to that expressed by the pressure volume plot? (A) Temperature - entropy (B) Temperature - pressure (C) Enthalpy - entropy

Last Answer : (A) Temperature - entropy

Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant  (a) pressure  (b) temperature  (c) volume  (d) internal energy  (e) entropy.

Description : Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant  (a) pressure  (b) temperature  (c) volume  (d) internal energy  (e) entropy.

Last Answer : Answer : a

Change in enthalpy of a system is the heat supplied at  (a) constant pressure  (b) constant temperature  (c) constant volume  (d) constant entropy  (e) N.T.P. condition.

Description : Change in enthalpy of a system is the heat supplied at  (a) constant pressure  (b) constant temperature  (c) constant volume  (d) constant entropy  (e) N.T.P. condition.

Last Answer : Answer : a

If value of n is infinitely large in a polytropic process pV” = C, then the process is known as constant  (a) volume  (b) pressure  (c) temperature  (d) enthalpy  (e) entropy

Description : If value of n is infinitely large in a polytropic process pV” = C, then the process is known as constant  (a) volume  (b) pressure  (c) temperature  (d) enthalpy  (e) entropy

Last Answer : Answer : a

Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure  (a) enthalpy  (b) volume  (c) mass  (d) entropy  (e) specific volume.

Description : Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure  (a) enthalpy  (b) volume  (c) mass  (d) entropy  (e) specific volume.

Last Answer : Answer : b

Which of the following is the property of a system  (a) pressure and temperature  (b) internal energy  (c) volume and density  (d) enthalpy and entropy  (e) all of the above.

Description : Which of the following is the property of a system  (a) pressure and temperature  (b) internal energy  (c) volume and density  (d) enthalpy and entropy  (e) all of the above.

Last Answer : Answer : e

During adiabatic, internally reversible process, what is true about the change in entropy?  A. It is temperature-dependent  B. It is always greater than zero  C. It is always zero  D. It is always less than zero

Description : During adiabatic, internally reversible process, what is true about the change in entropy?  A. It is temperature-dependent  B. It is always greater than zero  C. It is always zero  D. It is always less than zero

Last Answer : It is always zero

Which of the following processes is irreversible process  (a) isothermal  (b) adiabatic  (c) throttling  (d) all of the above  (e) none of the above.

Description : Which of the following processes is irreversible process  (a) isothermal  (b) adiabatic  (c) throttling  (d) all of the above  (e) none of the above.

Last Answer : Answer : c

If a fluid expands suddenly into vacuum through an orifice of large dimension, then such a process is called  (a) free expansion  (b) hyperbolic expansion  (c) adiabatic expansion  (d) parabolic expansion  (e) throttling.

Description : If a fluid expands suddenly into vacuum through an orifice of large dimension, then such a process is called  (a) free expansion  (b) hyperbolic expansion  (c) adiabatic expansion  (d) parabolic expansion  (e) throttling.

Last Answer : Answer : a

Entropy, which is a measure of the disorder of a system, is: (A) Independent of pressure (B) Independent of temperature (C) Zero at absolute zero temperature for a perfect crystalline substance (D) All (A), (B) & (C)

Description : Entropy, which is a measure of the disorder of a system, is: (A) Independent of pressure (B) Independent of temperature (C) Zero at absolute zero temperature for a perfect crystalline substance (D) All (A), (B) & (C)

Last Answer : (C) Zero at absolute zero temperature for a perfect crystalline substance

High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process: (A) Δ H = 0 and ΔS = 0 (B) Δ H ≠ 0 and ΔS = 0 (C) Δ H ≠ 0 and ΔS ≠ 0 (D) Δ H = 0 and ΔS ≠ 0

Description : High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process: ... (C) Δ H ≠ 0 and ΔS ≠ 0 (D) Δ H = 0 and ΔS ≠ 0

Last Answer : (B) Δ H ≠ 0 and ΔS = 0

Superheating of steam is done at constant (A) Enthalpy (B) Entropy (C) Pressure (D) Volume

Description : Superheating of steam is done at constant (A) Enthalpy (B) Entropy (C) Pressure (D) Volume

Last Answer : Option C

Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of (A) Solution (B) Vaporisation (C) Formation (D) Sublimation

Description : Entropy change of the reaction, H2O (liquid) → H2O (gas), is termed as the enthalpy of (A) Solution (B) Vaporisation (C) Formation (D) Sublimation

Last Answer : (B) Vaporisation

Mollier diagram is a plot of (A) Temperature vs. enthalpy (B) Temperature vs. enthalpy (C) Entropy vs. enthalpy (D) Temperature vs. internal energy

Description : Mollier diagram is a plot of (A) Temperature vs. enthalpy (B) Temperature vs. enthalpy (C) Entropy vs. enthalpy (D) Temperature vs. internal energy

Last Answer : (C) Entropy vs. enthalpy

Pick out the wrong statement. (A) The net change in entropy in any reversible cycle is always zero (B) The entropy of the system as a whole in an irreversible process increases (C) The entropy of the universe tends to a maximum (D) The entropy of a substance does not remain constant during a reversible adiabatic change

Description : Pick out the wrong statement. (A) The net change in entropy in any reversible cycle is always zero (B) The entropy of the system as a whole in an irreversible process increases (C) The ... to a maximum (D) The entropy of a substance does not remain constant during a reversible adiabatic change

Last Answer : (D) The entropy of a substance does not remain constant during a reversible adiabatic change

If the internal energy of an ideal gas decreases by the same amount as the work done by the system, then the (A) Process must be isobaric (B) Temperature must decrease (C) Process must be adiabatic (D) Both (B) and (C)

Description : If the internal energy of an ideal gas decreases by the same amount as the work done by the system, then the (A) Process must be isobaric (B) Temperature must decrease (C) Process must be adiabatic (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

The work done in an adiabatic change in a particular gas depends upon changes in the __________ only. (A) Temperature (B) Specific heat (C) Volume (D) Pressure

Description : The work done in an adiabatic change in a particular gas depends upon changes in the __________ only. (A) Temperature (B) Specific heat (C) Volume (D) Pressure

Last Answer : (A) Temperature

Which of the following statement is true? A. the chart is plotted for pressure equal to 760mm Hg B. the constant wbt line represents adiabatic saturation process C. the constant wbt line coincides with constant enthalpy line D. all of the mentioned

Description : Which of the following statement is true? A. the chart is plotted for pressure equal to 760mm Hg B. the constant wbt line represents adiabatic saturation process C. the constant wbt line coincides with constant enthalpy line D. all of the mentioned

Last Answer : ANSWER : D

For an ideal gas, the enthalpy (A) Increases with rise in pressure (B) Decreases with rise in pressure (C) Is independent of pressure (D) Is a path function

Description : For an ideal gas, the enthalpy (A) Increases with rise in pressure (B) Decreases with rise in pressure (C) Is independent of pressure (D) Is a path function

Last Answer : (C) Is independent of pressure

A ______ is a flow in which the gas flow is adiabatic and frictionless and entropy change is zero.  A. Isentropic flow  B. Isobaric flow  C. Steady flow  D. Uniform flow

Description : A ______ is a flow in which the gas flow is adiabatic and frictionless and entropy change is zero.  A. Isentropic flow  B. Isobaric flow  C. Steady flow  D. Uniform flow

Last Answer : Isentropic flow

Entropy of the system decreases, when (A) Snow melts into water (B) A gas expands spontaneously from high pressure to low pressure (C) Water is converted into ice (D) Both (B) & (C)

Description : Entropy of the system decreases, when (A) Snow melts into water (B) A gas expands spontaneously from high pressure to low pressure (C) Water is converted into ice (D) Both (B) & (C)

Last Answer : (D) Both (B) & (C)