19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
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…
If one monoatomic gas is expanded adiabatically from 2L to 10L at 1 atm external pressure then the value of U (in atm L) is
The magnitudes of enthalpy changes for irreversible adiabatic expansion of a gas from 1L to 2L is H₁ and for reversible adiabatic expansion for the same expansion is H₂. Then
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 ?
What is the entropy change in 2 mol N₂, when its temperature is taken from 400 K to 800 K. at constant pressure?
B. P G T 2. T C. P H S 3. -S D. H T P 4. P 5. V
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: For an isolated system, q is zero. Reason: In an isolated system, change in U and V is zero.
Assertion: Addition of Q and w gives ΔU. Reason: Addition of two path functions cannot give state function.
Assertion: Entropy of system increases for a spontaneous reaction. Reason: Enthalpy of reaction always not decreases for spontaneous reaction.
Find r S at 320 K for the reaction is:
Which of the following is a state function?
Calculate the mass of urea (NH₂CONH₂) required in making 0.25 molal aqueous solution using 2.5 L water. (Haryana PMT 2010)
Assertion: 1.575g H₂C₂O₄.2H₂O in 250 mL solution makes it 0.1 N. Reason : H₂C₂O₄.2H₂O is a dihydrate organic acid.
25.3 g of sodium carbonate, Na₂CO₃ is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ion and carbonate ions respectively are (Molar mass…
A solution contains non-volatile solute of molecular mass M2. Which of the following can be used to calculate the molecular mass of solute in terms of osmotic pressure? (Punjab PMET 2007) (a) m M VRT (b) m RT M V (c) …
At o 25 C, the total pressure of an ideal solution obtained by mixing 3 moles of ‘A’ and 2 moles of ‘B’, is 184 torr. What is the vapour pressure (in torr) of pure ‘B’ at the same temperature? (Vapour pressure of pure…
60 mL of N/5 H₂SO₄, 10 mL of N/2 HNO₃ and 30 mL of N/10 HCl are mixed together. The strength of the resulting mixture is (UP CPMT 2009)
An aqueous solution is 1.0 molal in KI. Which change will cause the vapour pressure of the solution to increase? (AIPMT 2010)
If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water ( Tf), when 0.01 mole of sodium sulphate is dissolved in 1 kg of water, …
0.01 M solution each of urea, common salt and Na₂SO₄ are taken, the ratio of depression of freezing point is
If is degree of dissociation of Na₂SO₄, the van’t Hoff’s factor, i, used for calculating the molar mass is
Which of the following pair of solutions are expected to be isotonic at the same temperature?
Four solutions of K₂SO₄ with the following concentration 0.1 m, 0.01 m, 0.001 m and 0.0001 m SOLUTIONS are available. The maximum value of van’t Hoff factor, i, corresponds to
Van’t Hoff factor of Ca (NO₃)₂ is