19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
The correct option for free expansion of an ideal gas under adiabatic condition is. (NEET 2020)
Entropy is a measure of
Which of the following statements is not correct?
The respective examples of extensive and intensive properties are
Enthalpy change for the reaction, 4H(g) → 2H₂(g) is – 869.5 kJ. The dissociation energy of H–H bond is
Which of the following reactions define o f G ? (a) diamond C O g CO g → (b) H g F g HF g → (c) H P O H O 2H PO → (d) SO g O g SO g →
The standard free energy change G is related to K (equilibrium constant) as
2 moles of ideal gas at 27°C temperature is expanded reversibly from 2 lit. to 20 lit. find entropy change. (R = 2 cal/mol K)
In which of the following cases, the reaction is spontaneous at all temperatures ?
H and E for the reaction, Fe O s 3H g 2Fe s H O l → at constant temperature are related as (a) H E (b) H E RT (c) H E RT (d) H E 3RT
Entropy of the universe is
The densities of graphite and diamond at 298 K are 2.25 and 3.31 g cm–3, respectively. If the standard free energy difference is equal to 1895 J mol–1, the pressure at which graphite will be transformed into diamond a…
A reaction occurs spontaneously if (2005)
Cell reaction is spontaneous when (a) G is negative (b) G is positive (c) red G is positive (d) red G is negative
Which of the following processes is a non-spontaneous process?
Which law states that entropy of all pure crystalline solids is zero at absolute zero?
For irreversible expansion of an ideal gas under isothermal condition, the correct option is (NEET 2021)
It is impossible for a reaction to take place if (a) H is +ve and S is +ve (b) H is –ve and S is +ve (c) H is +ve and S is –ve (d) H is –ve and S is –ve
Which of the following processes is irreversible?
In an isothermal expansion of an ideal gas
A system absorbs 10 kJ of heat and does 4 kJ of work. The internal energy of the system
Pick out the wrong statement
Which of the following processes is reversible?
In thermodynamics a process is called reversible when
A thermally isolated gaseous system can exchange energy with the surroundings. The mode of energy may be