19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0°C is (2012)
When ice melts into water, entropy
The heat of formation of Fe O s is –824.2 kJ mol–1. ∆H for the reaction. 2Fe O s 4Fe s 3O g → is:
The heat of combustion of carbon to CO₂ is –393.5 kJ/mol. The heat released upon formation of 35.2 g of CO₂ from carbon and oxygen gas is (2015)
For a sample of perfect gas when its pressure is changed isothermally from pi to pf, the entropy change is given by. (NEET-II 2016)
Entropy of the universe is
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?
In a reaction P + Q → R + S, there is no change in entropy. Enthalpy change for the reaction (∆H) is 12 kJ mol–1. Under what conditions, reaction will have negative value of free energy change?
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 →
Enthalpy change for the reaction, 4H(g) → 2H₂(g) is – 869.5 kJ. The dissociation energy of H–H bond is
In an isothermal expansion of an ideal gas
Under isothermal conditions, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is [Given that 1 L bar = 100 J] (NEET 2019)
An ideal gas expands isothermally from 10–3 m3 to 10–2 m3 at 300 K against a constant pressure of 105 N m–2. The work done on the gas is (Odisha NEET 2019)
Cell reaction is spontaneous when (a) G is negative (b) G is positive (c) red G is positive (d) red G is negative
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
A system absorbs 10 kJ of heat and does 4 kJ of work. The internal energy of the system
Which of the following processes is reversible?
The enthalpy of vaporisation of a compound AB at its boiling point (127°C) is 6.4 kJ mol-1. Its entropy of vaporization is
Regarding the internal energy of the molecule, which of the following statement is correct?
Internal energy is the sum of
Which of the following processes is irreversible?
The volume of gas is reduced to half from its original volume. The specific heat will____.
Tea placed in thermos flask is an example of
Which of the following is not an intensive property?
Which of the following is a state variable?