If the enthalpy of vaporisation of water is `186.5 J mol^(-1)`, then entropy of its vaporisation will be

If the enthalpy of vaporisation of water is `186.5 J mol^(-1)`, then entropy of its vaporisation will be
by

1 Answer

Answer :

If the enthalpy of vaporisation of water is `186.5 J mol^(-1)`, then entropy of its vaporisation will be A. `0.5 ... (-1)` D. `2.0KJK^(-1)"mole"^(-1)`
by

Related questions

Calculate the enthalpy of vaporisation per mole for ethanol. Given `DeltaS = 109.8 J K^(-1) mol^(-1)` and boiling point of ethanol is `78.5^(@)`.

Description : Calculate the enthalpy of vaporisation per mole for ethanol. Given `DeltaS = 109.8 J K^(-1) mol^(-1)` and boiling point of ethanol is `78.5^(@)`.

Last Answer : Calculate the enthalpy of vaporisation per mole for ethanol. Given `DeltaS = 109.8 J K^(-1) mol^(-1)` ... KJ mol^(-1)` D. Some more data is required

If a reaction has an enthalpy of -54.32 kJ/mol and an entropy of -354.2 J/(K*mol), what is the Gibbs free Energy at 54.3(degrees c)?

Description : If a reaction has an enthalpy of -54.32 kJ/mol and an entropy of -354.2 J/(K*mol), what is the Gibbs free Energy at 54.3(degrees c)?

Last Answer : DeltaG = DeltaH - TDeltaS dG = -54.32 kJ/mol - (54'32+273)K(-354.2J/molK) NB Thevtemperature is quoted in Kelvin(K) and the Entropy must be converted to kJ by dividing by '1000'/ Hence dG = ... 115.94 kJ/mol dG = (+)61.61 kJ/mol Since dG is positive, the reaction is NOT thermodynamically feasible.

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

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

The enthalpy change for a given reaction at `298 K` is `-x cal mol^(-1)`. If the reaction occurs spontaneously at `298 K`, the entropy change at that

Description : The enthalpy change for a given reaction at `298 K` is `-x cal mol^(-1)`. If the reaction occurs spontaneously at `298 K`, the entropy change at that

Last Answer : The enthalpy change for a given reaction at `298 K` is `-x cal mol^(-1)`. If the reaction occurs ... (-1)` C. Cannot be negative D. Cannot be positive

The enthalpy and entropy change for the reaction, `Br_(2)(l)+Cl_(2)(g)rarr2BrCl(g)` are `30KJmol^(-1)` and `105JK^(-1)mol^(-1)` respectively. The temp

Description : The enthalpy and entropy change for the reaction, `Br_(2)(l)+Cl_(2)(g)rarr2BrCl(g)` are `30KJmol^(-1)` and `105JK^(-1)mol^(-1)` respectively. The temp

Last Answer : The enthalpy and entropy change for the reaction, `Br_(2)(l)+Cl_(2)(g)rarr2BrCl(g)` are `30KJmol^(-1)` and ` ... 285.7 K B. 273 K C. 450 K D. 300 K

`DeltaH_"vaporisation"` (KJ/mol) are given for the hydrides of halogens in the following graph. The hydride HF will correspond to

Description : `DeltaH_"vaporisation"` (KJ/mol) are given for the hydrides of halogens in the following graph. The hydride HF will correspond to

Last Answer : `DeltaH_"vaporisation"` (KJ/mol) are given for the hydrides of halogens in the following graph. The hydride HF will ... . (B)Q C. (C)R D. (D)S

The correct order of enthalpy of vaporisation of noble gases is

Description : The correct order of enthalpy of vaporisation of noble gases is

Last Answer : The correct order of enthalpy of vaporisation of noble gases is A. `Xe gt Kr gt Ar Ne gt He` B. `Xe gt Ar ... gt Xe` D. `Ne gt Xe gt Kr gt He gt Ar`

Which of the following assumes constant molal vaporisation and overflow?(A) McCabe-Thiele method (B) Ponchan-Savarit method (C) Enthalpy concentration method (D) Plate absorption column

Description : Which of the following assumes constant molal vaporisation and overflow? (A) McCabe-Thiele method (B) Ponchan-Savarit method (C) Enthalpy concentration method (D) Plate absorption column

Last Answer : (A) McCabe-Thiele method

Pick out the wrong statement. (A) Minimum number of degree of freedom of a system is zero (B) Degree of freedom of a system containing a gaseous mixture of helium, carbon dioxide and hydrogen is 4 (C) For a two phase system in equilibrium made up of fourchemical species, the number of degrees of freedom is 4 (D) Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation

Description : Pick out the wrong statement. (A) Minimum number of degree of freedom of a system is zero (B) Degree of freedom of a system containing a gaseous mixture of helium, carbon ... ) Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation

Last Answer : (D) Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation

At normal boiling point, molar entropy of vaporisation is __________ Joule/K°.mole. (A) 72 (B) 92 (C) 142 (D) 192

Description : At normal boiling point, molar entropy of vaporisation is __________ Joule/K°.mole. (A) 72 (B) 92 (C) 142 (D) 192

Last Answer : (B) 92

_________ does not change during phase transformation processes like sublimation, melting & vaporisation. (A) Entropy (B) Gibbs free energy (C) Internal energy (D) All (A), (B) & (C)

Description : _________ does not change during phase transformation processes like sublimation, melting & vaporisation. (A) Entropy (B) Gibbs free energy (C) Internal energy (D) All (A), (B) & (C)

Last Answer : (B) Gibbs free energy

The enthalpy changes at 298 K in successive breaking of `O-H` bonds of water, are `H_(2)O(g) rarr H(g)+OH(g),DeltaH=498kJ mol^(-1)` `OH(g) rarr H(g)+O

Description : The enthalpy changes at 298 K in successive breaking of `O-H` bonds of water, are `H_(2)O(g) rarr H(g)+OH(g),DeltaH=498kJ mol^(-1)` `OH(g) rarr H(g)+O

Last Answer : The enthalpy changes at 298 K in successive breaking of `O-H` bonds of water, are `H_(2)O(g) rarr H(g)+OH(g), ... KJ mol"^(-1)` D. `463 "KJ mol"^(-1)`

`Delta_(f)^(@)` for `CO_(2(g)), CO_((g))` and `H_(2)O_((g))` are `-393.5,-110.5` and `-241.8kJ mol^(-1)` respectively. The standard enthalpy change `(

Description : `Delta_(f)^(@)` for `CO_(2(g)), CO_((g))` and `H_(2)O_((g))` are `-393.5,-110.5` and `-241.8kJ mol^(-1)` respectively. The standard enthalpy change `(

Last Answer : `Delta_(f)^(@)` for `CO_(2(g)), CO_((g))` and `H_(2)O_((g))` are `-393.5,-110.5` and `-241.8kJ mol^(-1 ... A. `524.1` B. `41.2` C. `-262.5` D. `-41.2`

Given that standard heat enthalpy of `CH_(4), C_(2)H_(4)` and `C_(3)H_(8)` are -17.9, 12.5, -24.8 Kcal/mol. The `Delta H` for `CH_(4)+C_(2)Hrarr C_(3)

Description : Given that standard heat enthalpy of `CH_(4), C_(2)H_(4)` and `C_(3)H_(8)` are -17.9, 12.5, -24.8 Kcal/mol. The `Delta H` for `CH_(4)+C_(2)Hrarr C_(3)

Last Answer : Given that standard heat enthalpy of `CH_(4), C_(2)H_(4)` and `C_(3)H_(8)` are -17.9, 12.5, -24.8 Kcal ... . `-30.2` Kcal C. 55.2 Kcal D. `-19.4` Kcal

The value of enthalpy change `(DeltaH)` for the reaction `C_(2)H_(5)OH (l)+3O_(2) (g) rarr 2CO_(2) (g) +3H_(2)O (l)` at `27^(@)C` is `-1366.5 kJ mol^(

Description : The value of enthalpy change `(DeltaH)` for the reaction `C_(2)H_(5)OH (l)+3O_(2) (g) rarr 2CO_(2) (g) +3H_(2)O (l)` at `27^(@)C` is `-1366.5 kJ mol^(

Last Answer : The value of enthalpy change `(DeltaH)` for the reaction `C_(2)H_(5)OH (l)+3O_(2) (g) rarr 2CO_(2) (g) + ... 1369. kJ` C. `-1364.0 kJ` D. `-1361.5 kJ`

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

If the enthaply change for the transition of liquid water to steam is 30 KJ `"mol"^(-1)` at `27^(@)` C . The entropy change for the process would be

Description : If the enthaply change for the transition of liquid water to steam is 30 KJ `"mol"^(-1)` at `27^(@)` C . The entropy change for the process would be

Last Answer : If the enthaply change for the transition of liquid water to steam is 30 KJ `"mol"^(-1)` at `27^(@)` C . The ... K^(-1)` D. `100 J mol^(-1)K^(-1)`

Given standard enthalpy of formation of `CO(-110 "KJ mol"^(-1))` and `CO_(2)(-394 "KJ mol"^(-1))`. The heat of combustion when one mole of graphite bu

Description : Given standard enthalpy of formation of `CO(-110 "KJ mol"^(-1))` and `CO_(2)(-394 "KJ mol"^(-1))`. The heat of combustion when one mole of graphite bu

Last Answer : Given standard enthalpy of formation of `CO(-110 "KJ mol"^(-1))` and `CO_(2)(-394 "KJ mol"^(-1))`. The heat ... B. `-284` KJ C. `-394` KJ D. `-504` KJ

The enthalpy of combustion of `H_(2)` , cyclohexene `(C_(6)H_(10))` and cyclohexane `(C_(6)H_(12))` are `-241` , `-3800` and `-3920KJ` per mol respect

Description : The enthalpy of combustion of `H_(2)` , cyclohexene `(C_(6)H_(10))` and cyclohexane `(C_(6)H_(12))` are `-241` , `-3800` and `-3920KJ` per mol respect

Last Answer : The enthalpy of combustion of `H_(2)` , cyclohexene `(C_(6)H_(10))` and cyclohexane `(C_(6)H_(12))` are `-241 ... "KJ mol"^(-1)` D. `242 "KJ mol^(-1)`

The enthalpy of formation of ammonia is `-46.0 KJ mol^(-1)` . The enthalpy change for the reaction `2NH_(3)(g)rarr N_(2)(g)+3H_(2)(g)` is :

Description : The enthalpy of formation of ammonia is `-46.0 KJ mol^(-1)` . The enthalpy change for the reaction `2NH_(3)(g)rarr N_(2)(g)+3H_(2)(g)` is :

Last Answer : The enthalpy of formation of ammonia is `-46.0 KJ mol^(-1)` . The enthalpy change for the reaction `2NH_(3)(g) ... mol^(-1)` D. `-92.0 KJ mol^(-1)`

The enthalpy of formation of `CO(g), CO_(2)(g),N_(2)O(g)` and `N_(2)O_(4)(g)` is `-110,-393,+81` and 10 kJ / mol respectively. For the reaction `N_(2)

Description : The enthalpy of formation of `CO(g), CO_(2)(g),N_(2)O(g)` and `N_(2)O_(4)(g)` is `-110,-393,+81` and 10 kJ / mol respectively. For the reaction `N_(2)

Last Answer : The enthalpy of formation of `CO(g), CO_(2)(g),N_(2)O(g)` and `N_(2)O_(4)(g)` is `-110,-393,+81` and 10 ... is A. `-212` B. `+212` C. `+778` D. `-778`

Standard enthalpy of formation of ethane is -84.7kjper mol calculate the enthalpy change for the formation of 0.1kg ethane

Description : Standard enthalpy of formation of ethane is -84.7kjper mol calculate the enthalpy change for the formation of 0.1kg ethane

Last Answer : Standard enthalpy of formation of ethane is -84.7kjper mol calculate the enthalpy change for the formation of 0.1kg ethane

Ionization enthalpy of Li is 520 kJ mol^(-1) while that of F is 1681 kJ mol^(-1) . Explain.

Description : Ionization enthalpy of Li is 520 kJ mol^(-1) while that of F is 1681 kJ mol^(-1) . Explain.

Last Answer : Ionization enthalpy of Li is 520 kJ mol-1 while that of F is 1681 kJ mol-1. Explain.

Standard entropy of `X_(2)` , `Y_(2)` and `XY_(3)` are `60, 40 ` and `50JK^(-1)mol^(-1)` , respectively. For the reaction, `(1)/(2)X_(2)+(3)/(2)Y_(2)r

Description : Standard entropy of `X_(2)` , `Y_(2)` and `XY_(3)` are `60, 40 ` and `50JK^(-1)mol^(-1)` , respectively. For the reaction, `(1)/(2)X_(2)+(3)/(2)Y_(2)r

Last Answer : Standard entropy of `X_(2)` , `Y_(2)` and `XY_(3)` are `60, 40 ` and `50JK^(-1)mol^(-1)` , respectively ... be: A. 500 K B. 750 K C. 1000 K D. 1250 K

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

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

What is defined as the sum of the system’s internal energy and the product of its pressure and volume? a. Entropy. b. Enthalpy. c. Free energy. d. Potential energy.

Description : What is defined as the sum of the system’s internal energy and the product of its pressure and volume? a. Entropy. b. Enthalpy. c. Free energy. d. Potential energy.

Last Answer : b. Enthalpy.

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.

Assertion: The enthalpy of formation of gaseous oxygen molecules at `298K` and under1 atm is zero. Reason: The entropy of formation of gaseous oxygen

Description : Assertion: The enthalpy of formation of gaseous oxygen molecules at `298K` and under1 atm is zero. Reason: The entropy of formation of gaseous oxygen

Last Answer : Assertion: The enthalpy of formation of gaseous oxygen molecules at `298K` and under1 atm is zero. ... D. If both Assertion & Reason are false.

Assertion (A): Enthalpy of graphite is lower than that of diamond. Reason (R ) : Entropy of graphite is lower than that of diamond.

Description : Assertion (A): Enthalpy of graphite is lower than that of diamond. Reason (R ) : Entropy of graphite is lower than that of diamond.

Last Answer : Assertion (A): Enthalpy of graphite is lower than that of diamond. Reason (R ) : Entropy of ... False. D. If both Assertion & Reason are false.

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

The heat content of air is called the _____ of the air. a. Temperature b. Humidity c. Enthalpy d. Psychrometry e. Entropy

Description : The heat content of air is called the _____ of the air. a. Temperature b. Humidity c. Enthalpy d. Psychrometry e. Entropy

Last Answer : ANSWER : C

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.

_____ is the amount of uncertainty in a system of symbols A. Bandwidth B. Enthalpy C. Entropy D. Quantum

Description : _____ is the amount of uncertainty in a system of symbols A. Bandwidth B. Enthalpy C. Entropy D. Quantum

Last Answer : C. Entropy

What is meant by entropy driven reaction? How can the reaction with positive change of enthalpy and entropy be made entropy driven?

Description : What is meant by entropy driven reaction? How can the reaction with positive change of enthalpy and entropy be made entropy driven?

Last Answer : Ans.The free energy change of a reaction is given by ΔG = ΔH - TΔS For a reaction to be spontaneous, ΔG should be -ve. If both ΔH and ΔS are positive ΔG can be -ve if TΔS>ΔH in magnitude. Thus, entropy ... is low, TΔS should be greater than ΔH (ii) If ΔS is small, T should be so large that TΔS>ΔH.

(i)State why heat changes in physical and chemical processes are indicated by enthalpy changes and not by entropy changes? (ii)What are the limitations of First Law of thermodynamics?

Description : (i)State why heat changes in physical and chemical processes are indicated by enthalpy changes and not by entropy changes? (ii)What are the limitations of First Law of thermodynamics?

Last Answer : (i) Most of the processes are carried out in an open system i.e, at constant pressure. (ii)(a) Can’t explain the feasibility of the reaction. (b)It poses no restriction on the direction of flow of heat. (c)Practically it is not possible to convert the heat energy into an equivalent amount of work.

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

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

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

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

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

Last Answer : (D) Pressure

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

The extensive properties are (A) Volume, mass and number of moles (B) Free energy, entropy and enthalpy (C) Both (A) and (B) (D) None of these

Description : The extensive properties are (A) Volume, mass and number of moles (B) Free energy, entropy and enthalpy (C) Both (A) and (B) (D) None of these

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

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

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

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

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