Thermodynamics · Question 4

A protein undergoes reversible thermal denaturation from its initial state N to denatured state D according to N D. At 60 C, the concentrations of both N and D are equal at equilibrium, and the standard enthalpy change of denaturation is 666 kJ mol-1. The standard entropy change ( S in kJ K-1 mol-1) of the protein upon denaturation at 60 C is closest to

1. 11.1
2. 2.0
3. 2000.0
4. 333.0

The standard heat of formation, in kcal/mol of Ba2+ is : [Given : standard heat of formation of SO42- ion (aq) = -216 kcal/mol, standard heat of crystallisation of BaSO4(s) = -4.5 kcal/mol, standard heat of formation of BaSO4(s) = -349 kcal/mol]

1. +133.0
2. +220.5
3. -128.5
4. -133.0

C(s) + 2H2(g) CH4(g); H = -74.8 kJ mol-1. Which of the following diagrams gives an accurate representation of the above reaction? [R reactants; P products]

1. [figure]
2. [figure]
3. [figure]
4. [figure]

In which of the following processes entropy increases? Choose the correct answer from the options given below:

1. A and C
2. A, B and D
3. A, C and D
4. C and D

Match List I with List II. Choose the correct answer from the options given below:

1. A-IV, B-III, C-II, D-I
2. A-IV, B-II, C-III, D-I
3. A-I, B-II, C-III, D-IV
4. A-II, B-III, C-IV, D-I

The work done during reversible isothermal expansion of one mole of hydrogen gas at 25 from pressure of 20 atmosphere to 10 atmosphere is (Given R = 2.0 cal K-1 mol-1)

1. 0 calorie
2. -413.14 calories
3. 413.14 calories
4. 100 calories

Choose the correct statement for the work done in the expansion and heat absorbed or released when 5 litres of an ideal gas at 10 atmospheric pressure isothermally expands into vacuum until volume is 15 litres :

1. Both the heat and work done will be greater than zero
2. Heat absorbed will be less than zero and work done will be positive
3. Work done will be zero and heat will also be zero
4. Work done will be greater than zero and heat will remain zero

For an endothermic reaction: Choose the correct answer from the options given below:

1. B and D
2. C and D
3. A and B
4. A and C

For the following reaction at 300 K A2(g) + 3B2(g) 2AB3(g) the enthalpy change is +15 kJ, then the internal energy change is :

1. 19988.4 J
2. 200 J
3. 1999 J
4. 1.9988 kJ

Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?

1. H = U + ng RT
2. H - U = - n RT
3. H + U = n R
4. H = U - ng RT