मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

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

Advertisements
Advertisements

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
Advertisements

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.
shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Chemical Thermodynamics - Exercises [पृष्ठ ८६]

APPEARS IN

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

संबंधित प्रश्‍न

Define entropy.


Answer the following in one or two sentences.

If the enthalpy change of a reaction is ∆H how will you calculate the entropy of surroundings?


Answer the following question.

Although ΔS for the formation of two moles of water from H2 and O2 is –327J K–1, it is spontaneous. Explain.
(Given ΔH for the reaction is –572 kJ).


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?


Equilibrium constant for a reaction is 20. What is the value of ΔG° at 300 K? (R = 8 x 10-3 kJ)


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 ____________.


A system is changed from an initial state to a final state by a manner such that ∆H = Q. If the change from initial state to final state was made by a different path, then ____________.


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)


What is the entropy change (in J K−1 mol−1) when one mole of ice is converted into water at 0°C? (The enthalpy change for the conversion of ice to liquid water is 6.0 kJ mol−1 at 0°C)


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


For the reaction:

\[\ce{2Cl_{(g)} -> Cl2_{(g)}}\]


Which one of the following has ΔS0 greater than zero?


For the following reaction:

\[\ce{Fe2O3_{(s)} + 3CO_{(g)} -> 2Fe_{(s)} + 3CO2_{(g)}}\]; ΔH0 = −29.8 kJ and ΔS0 = 15 J K−1. What is the value of \[\ce{ΔS_{(total)}}\] at 298 K?


Which of the following conditions indicates the reaction is spontaneous?


Equilibrium constant for a reaction is 20. What is the value of ∆G0 at 300 K? (R = 8 × 10−3 kJ)


At what temperature, a chemical reaction will have the following values of ∆G, ∆S and ∆H?

∆G = −5.2 KJ mol−1, ∆H = 145.6 kJ mol−1, ∆S = −216 kJ mol−1


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?


Which of following is residual entropy of a substance?


Identify the unit used for measurement of energy according to international system of units?


A reaction is spontaneous at low temperatures but non-spontaneous at high temperatures. Which of the following is true for the reaction?


Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are −382.64 kJ mol−1 and −145.6 JK−1 mol−1, respectively. Standard Gibb's energy change for the same reaction at 298 K 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.


Write the relationship between Gibbs energy change for a process and total entropy change of system and surroundings.


For a certain reaction ΔH0 is −224 kJ and ΔS0 is −153 J K−1. At what temperature the change over from spontaneous to non-spontaneous will occur?


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.


Define second law of thermodynamics.


The entropy of vaporisation of benzene is 85 J K−1 mol−1. When 117 g of benzene vaporises at its boiling point, what is the entropy change of the surroundings if the process is at equilibrium?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×