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

Consider the following statements:

(i) Crystallisation is accompanied by decrease in entropy,
(ii) Spontaneous process is an irreversible process and cannot be reversed by external agency,
(iii) The enthalpies of formation for all elements in their standard state are zero.

Identify the correct statements.

33.33% studentsanswered this correctly

Important Questions on Thermodynamics

HARD

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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)

HARD

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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

)

EASY

Chemistry>Physical Chemistry>Thermodynamics>Entropy and Second Law of Thermodynamics

For the reaction,

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

, the correct option is

EASY

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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:

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Entropy and Second Law of Thermodynamics

The process with negative entropy change is:

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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>Thermodynamics>Entropy and Second Law of Thermodynamics

The true statement amongst the following is:

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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

EASY

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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>Thermodynamics>Entropy and 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-

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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 $298 K$ ?

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Entropy and Second Law of Thermodynamics

For which of the following processes,

∆ S

is negative?

HARD

Chemistry>Physical Chemistry>Thermodynamics>Entropy and 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: