English
Tamil Nadu Board of Secondary EducationHSC Science Class 11

What is the usual definition of entropy?

Advertisements
Advertisements

Question

What is the usual definition of entropy?

Short/Brief Note
Advertisements

Solution

  1. Entropy is a thermodynamic state function that is a measure of the randomness or disorderliness of the system.
  2. For a reversible change taking place at a constant temperature (T). the change in entropy
  3. The system is equal to heat energy absorbed or evolved (q) by the system divided by the constant temperature (T).
    `Δ"S"_"sys" = "q"_"rev"/"T"`
shaalaa.com
Various Statements of the Second Law of Thermodynamics
  Is there an error in this question or solution?
Chapter 7: Thermodynamics - Evaluation [Page 224]

APPEARS IN

Samacheer Kalvi Chemistry - Volume 1 and 2 [English] Class 11 TN Board
Chapter 7 Thermodynamics
Evaluation | Q II. 5. a. | Page 224

RELATED QUESTIONS

The correct thermodynamic conditions for the spontaneous reaction at all temperature is


∆S is expected to be maximum for the reaction


Identify the state and path functions out of the following:

  1. Enthalpy
  2. Entropy
  3. Heat
  4. Temperature
  5. Work
  6. Free energy

State the various statements of the second law of thermodynamics.


1 mole of an ideal gas, maintained at 4.1 atm and at a certain temperature, absorbs heat 3710 J and expands to 2 litres. Calculate the entropy change in the expansion process.


You are given normal boiling points and standard enthalpies of vapourisation. Calculate the entropy of vapourisation of liquids listed below.

Liquid Boiling points (°C) ΔH (kJ mol−1)
Ethanol 78.4 + 42.4

You are given normal boiling points and standard enthalpies of vapourisation. Calculate the entropy of vapourisation of liquids listed below.

Liquid Boiling points (°C) ΔH (kJ mol−1)
Toluene 110.6 + 35.2

Cyanamide (NH2CN) is completely burnt in excess oxygen in a bomb calorimeter, ΔU was found to be −742.4 kJ mol−1, calculate the enthalpy change of the reaction at 298 K.\[\ce{NH2CN_{(s)} + 3/2 O2_{(g)} -> N2_{(g)} + CO2_{(g)} + H2O_{(l)}}\] ΔH = ?


Calculate the enthalpy of hydrogenation of ethylene from the following data.

Bond energies of C − H, C − C, C = C and H − H are 414, 347, 618 and 435 kJ mol−1.


For the reaction at 298 K: \[\ce{2A + B -> C}\]

ΔH = 400 KJ mol−1; ΔS = 0.2 KJ K−1 mol−1 Determine the temperature at which the reaction would be spontaneous.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×