For the process H 2 O l → H 2 O g at T = 100 o C and 1 atmosphere pressure, the correct choice is-

∆ S s y s t e m > 0 a n d ∆ S s u r r o u n d i n g < 0

∆ S s y s t e m > 0 a n d ∆ S s u r r o u n d i n g > 0

∆ S s y s t e m < 0 a n d ∆ S s u r r o u n d i n g > 0

∆ S s y s t e m < 0 ∆ S s u r r o u n d i n g < 0

MEDIUM

Earn 100

Derive the formula for entropy change during mixing of ideal gases at constant temperature and pressure.

Important Questions on Chemical Thermodynamics

HARD

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The entropy change associated with the conversion of

1 k g

of ice at

273 K

to water vapours at

383 K

is:

(Specific heat of water liquid and water vapour are

4.2 k J K^{-}

and

2.0 k J K^{- 1} k g^{- 1}

; heat of liquid fusion and vaporization of water are

334 k J k g^{- 1}

and

2491 k J k g^{- 1}

, respectively). (

l o g

273 = 2.436, \log 373 = 2.572, \log 383 = 2.583

)

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The process with negative entropy change is:

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The true statement amongst the following is:

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

Which of the following show an increase in entropy?

I. Boiling of water

II. Melting of ice

III. Freezing of water

IV. Formation of hydrogen gas from water

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The entropy change in the isothermal reversible expansion of 2 moles of an ideal gas from 10 to 100 at 300 K is

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

Calculate the entropy change in melting

1

mole of ice at

273 K ({ΔH}_{f}^{°} = 6.025 kJ {mol}^{- 1})

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

In which case change in entropy is negative?

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

Standard molar entropy is

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The latent heat of melting of ice at

0 ° C is 6 kJ {mol}^{- 1}

. The entropy change during the melting in

J K^{- 1} {mol}^{- 1}

is closets to-

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For the process

H_{2} O (l) \to H_{2} O (g)

T = 100^{o} C

and

1

atmosphere pressure, the correct choice is-

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

When the same quantity of heat is absorbed by a system at two different temperatures

T_{1}

and

T_{2}

, such that

T_{1} > T_{2}

, change in entropies are

Δ S_{1}

and

Δ S_{2}

respectively. Then:

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For a sample of perfect gas, when its pressure is changed isothermally from

p_{i}

p_{f}

, the entropy change is given by

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For the following reaction

${Fe}_{2} O_{3 (s)} + 3 {CO}_{(g)} ⟶ 2 {Fe}_{(s)} + 3 {CO}_{2 (g)} ΔH ° = - 29.8 kJ$ and $ΔS ° = 15 {JK}^{- 1}$ . What is the value of ${ΔS}_{(total)}$ at $298 K$ ?

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For the reaction,

2 Cl (g) \to {Cl}_{2} (g)

, the correct option is

HARD

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

A container is divided into two compartments by a removable partition as shown below:

Question Image

In the first compartment, $n_{1}$ moles of ideal gas He is present in a volume $V_{1} .$ In the second compartment, $n_{2}$ moles of ideal gas $Ne$ is present in a volume $V_{2} .$ The temperature and pressure in both the compartments are $T$ and $P,$ respectively. Assuming $R$ is the gas constant, the total change in entropy upon removing the partition when the gases mix irreversibly is:

EASY

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

The volume of one mole of an ideal gas is increased to

10

times of its initial volume isothermally and reversibly. The change in entropy is

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

During which of the following processes, does entropy decrease ?

(A) Freezing of water to ice at $0 ° C$
(B) Freezing of water to ice at $- 10 ° C$
(C) $N_{2} (g) + 3 H_{2} (g) \to 2 {NH}_{3} (g)$
(D) Adsorption of $CO (g)$ and lead surface
(E) Dissolution of $NaCl$ in water

HARD

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For a reaction taking place in a container in equilibrium with its surroundings, the effect of temperature on its equilibrium constant

K

in terms of change in entropy is described by:

MEDIUM

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

For which of the following processes,

∆ S

is negative?

HARD

Chemistry>Physical Chemistry>Chemical Thermodynamics>Second Law of Thermodynamics

One mole of an ideal gas at

300 K

in thermal contact with its surroundings expands isothermally from

1.0 L

2.0 L

against a constant pressure of

3.0 atm

. In this process, the change in entropy of the surroundings

(∆ S_{s u r r})

J K^{- 1}

is:

(1 L atm = 101.3 J)

Derive the formula for entropy change during mixing of ideal gases at constant temperature and pressure.

Important Questions on Chemical Thermodynamics

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