19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
A reaction having equal energies of activation for forward and reverse reactions has (NEET 2013)
Bond dissociation energy of CH₄ is 360 kJ/mol and C₂H₆ is 620 kJ/mol. Then bond dissociation energy of C – C bond is
Assertion: The extensive properties of a single pure substance will not only depend upon the number of moles of the substance present but also on any two of the three variables. Reason: Any extensive property if expre…
In endothermic reactions,
For which of the following cases H S T ?
B. P G T 2. T C. P H S 3. -S D. H T P 4. P 5. V
Assertion: There is no change in internal energy for an ideal gas at constant temperature. Reason: Internal energy of an ideal gas is a function of temperature only.
What is the entropy change in JK–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)
Assertion: In isothermal process, whole of heat energy supplied to the system is converted into internal energy. Reason: According to the first law of thermodynamics U = q - w
For a reaction: X → Y + Z absolute entropies are X = 120 JK–1 mol–1 Y = 213.8 JK–1 mol–1 and Z = 197.9 JK–1 mol–1. What will be the entropy change at 298 K and 1 atm?
Which of the following macroscopic variable is not measurable?
Thermodynamics deals with
The enthalpy of vaporisation of a substance is 8400 J mol–1 and its boiling point is –173ºC. The entropy change for vaporisationis :
When 1 mol of an ideal gas is compressed to half of its volume, its temperature becomes double; then the change in entropy (S) would be:
Consider the reaction below at 298 K: C (graphite) + 2H₂ (g) → CH₄ (g) →fHº (kJ/mol) – 74.9 S₀ m(J/K/mol + 5.6 + 130.7 Which statement below is correct ?
Which of the following is an example of open system?
What is the entropy change in 2 mol N₂, when its temperature is taken from 400 K to 800 K. at constant pressure?
Assertion: For an isolated system, q is zero. Reason: In an isolated system, change in U and V is zero.
In an isobaric process, when temperature changes from 1T to T , S is equal to
Thermodynamically, the most stable form of carbon
Which of the following statements is correct for the spontaneous adsorption of a gas? (2014)
1 mole of an ideal gas expands isothermally reversibly from 2 litre to 4 litre and 3 moles of the same gas expands from 2 litre to x litre and doing same work, what is ‘x’?
A liquid which is confined inside an adiabatic piston is suddenly taken from state 1 to state 2 by a single stage process. If the piston comes to rest at point 2 as shown. Then the enthalpy change for the process will…
The respective examples of extensive and intensive properties are
A diatomic gas at pressure P, compressed adiabatically to half of its volume, what is the final pressure?