Chemistry Question Bank

Bond dissociation energy of CH₄ is 360 kJ/mol and C₂H₆ is 620 kJ/mol. Then bond dissociation energy of C – C bond is

Find rH at 320 K for the reaction is:

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

B. P G T 2. T C. P H S 3. -S D. H T P 4. P 5. V

Assertion: Addition of Q and w gives ΔU. Reason: Addition of two path functions cannot give state function.

Find r S at 320 K for the reaction is:

A system undergoes a 2-step process. In step 1, 15 J of work is done on the system as its internal energy increases by a total of 30 J. In step 2, at constant volume, the system decreases its internal energy by 20 J. …

A diatomic gas at pressure P, compressed adiabatically to half of its volume, what is the final pressure?

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:

In an isobaric process, when temperature changes from 1T to T , S is equal to

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

Assertion: For an isolated system, q is zero. Reason: In an isolated system, change in U and V is zero.

Assertion: A reaction which is spontaneous and accompanied by decrease of randomness must be exothermic. Reason: All exothermic reactions are accompanied by decrease in randomness.

Assertion: Entropy of system increases for a spontaneous reaction. Reason: Enthalpy of reaction always not decreases for spontaneous reaction.

Which thermodynamic parameter is not a state function?

A system undergoes a 3-step process. In step 1, 25 J of work is done by the system as its internal energy (U) decreases by 50 J. In step 2, w = -15J and q = +40J. In step 3 at constant volume, the system gives off 50 …

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 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

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, U and w correspond to

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?

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…

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.

The heat liberated when 1.89g of benzoic acid is burnt in a bomb calorimeter at 25 °C and it increases the temperature of 18.94 kg of water by 0.632 °C. if the specific heat of water at 25 °C is 0.998 cal/g- °C, the v…