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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

In which of the following, entropy of the system decreases? - Chemistry

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प्रश्न

In which of the following, entropy of the system decreases?

पर्याय

  • Crystallization of liquid into solid.

  • Temperature of crystalline solid is increased from 0 K to 115 K

  • H2(g) → 2H(g) 

  • 2 NaHCO3(s)  → Na2CO3(s) + CO2(g) + H2O(g)

MCQ

उत्तर

Crystallization of liquid into solid

Explanation:

  • A system's disorder or difficulty is measured by its entropy.
  • A liquid turns into a solid—a more ordered state—during the crystallisation process.
  • Because the particles become more organised and have less mobility, entropy consequently falls.
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Spontaneous (Irreversible) Process
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Chemical Thermodynamics - Exercises [पृष्ठ ८६]

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बालभारती Chemistry [English] 12 Standard HSC
पाठ 4 Chemical Thermodynamics
Exercises | Q 1.03 | पृष्ठ ८६

संबंधित प्रश्‍न

Define entropy.


Answer the following in one or two sentences.

Comment on the spontaneity of reactions for which ∆H is positive and ∆S is negative.


Obtain the relationship between ∆G° of a reaction and the equilibrium constant.


Answer in brief.

What is entropy? Give its units.


Answer the following question.

Obtain the relation between ΔG and `triangle "S"_"total"`. Comment on the spontaneity of the reaction.


For a certain reaction ΔH° = 219 kJ and ΔS° = –21 J/K. Determine whether the reaction is spontaneous or nonspontaneous.


Answer the following question.

Determine whether the following reaction is spontaneous under standard state conditions.

2H2O(l) + O2(g) → 2H2O2(l)

if ΔH° = 196 kJ, ΔS° = –126 J/K, does it have a cross-over temperature?


One mole of NaCl(s) on melting absorbed 30.5 kJ of heat and its entropy increased by 28.8 J K−1. The melting point of NaCl is ____________.


For a process, entropy change of a system is expressed as ________.


Arrange the following in order of increasing entropy.

I. 1.0 mol H2O (298 K, 1 atm)

II. 1.0 mol H2O (270 K, 1 atm)

III. 1.0 mol H2O (400 K, 1 atm)


In how many of the following, ∆S is positive?

i. Melting of ice

ii. Sublimation of iodine

iii. Dissolution of CuSO4 in water

iv. Condensation of water vapour

v. Dissociation of H2 molecule into atoms

vi. Conversion of carbon dioxide gas to dry ice

vii. Vaporization of acetone


In which of the following, ∆S is positive?


Heat of combustion of C(s), H2(g) and C2H6(g) are −x1, −x2 and −x3 respectively. Hence heat of formation of C2H6(g) is ____________.


Which of the following conditions indicates the reaction is spontaneous?


For a reaction to be non-spontaneous at all temperatures, values of ΔH and ΔS respectively are ____________.


If ΔH° and ΔS° for the reaction \[\ce{N2O_{4(g)} -> 2NO_{2(g)}}\] is 57.24 kJ and 175.8 JK-1 mol-1 respectively. What is the value of ΔG° for this reaction at 298 K?


Standard molar entropy is ______.


For a reaction ΔH = - 30kJ and ΔS = - 45 JK-1, at what temperature reaction changes from spontaneous to non-spontaneous?


When will be change in Gibb's free energy always negative?


Relation between ΔH and ΔU for the reaction, \[\ce{2SO_{3(g)} -> 2SO_{2(g)} + O_{2(g)}}\] is _______.


Write the correct condition for spontaneity in terms of Gibbs energy.


Identify whether the following pair have larger entropy or not. If yes then Why?

He(g) in a volume of 1 L or He(g) in a volume of 5 L both at 25°C.


Identify whether the following pair have a larger entropy or not. If yes then Why?

O2{g) at 1 atm or O2(g) at 10 atm both at the same temperature.


What is a spontaneous process? What are its characteristics?


Calculate ΔG0 for the reaction

\[\ce{CH_{4(g)} + H_{2(g)}-> C2H_{6(g)}}\]

State whether the reaction is spontaneous or not. (Given: KP = 3.358 × 1017, T = 25° C, R = 8.314 × 10−3 kJK−1 moI−1)


Find out the value of equilibrium constant for the following reaction at 298 K, \[\ce{2NH3_{(g)} + CO2_{(g)} ⇌ NH2 - COONH2_{(aq)} + H2O_{(l)}}\] Gibbs Standard energy change 298 K = –13.6 kJ mol−1.


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