Physical Chemistry Past Papers

[OBJECTIVE]

Subject: Chemistry-I (Physical Chemistry)

Time Allowed: 15 Min

Maximum Marks: 10

NOTE: Attempt this Paper on this Question Sheet only. Please encircle the correct option. Division of marks is given in front of each question. This Paper will be collected back after expiry of time limit mentioned above.

 

Part-I Encircle the right answer, cutting and overwriting is not allowed. (1×10=10)

  1. 1. The colloidal solution is a

(a) Heterogeneous                         (b) homogeneous

(c) True solution                               (d) None of these

  1. The units of 1st order rate constant are

(a) mmol-1                                           (b) sec-1

(c) m2mol-2                                          (d) mol m-2

  1. The Units of Michaelis-Menten constant (KM) are

(a) kg mol-1                                         (b) kg mol

(c) mol dm-3                                        (d) dm-3

  1. The entropy of universe is going to increase. This statement is called —

(a) 1st law of thermodynamics    (b) 2nd law of thermodynamics

(c) Zeroth law of thermodynamics           (d) None of these

  1. The Langmuir adsorption isotherm for adsorption of a gas on solid is It can be expressed as
  2. The Freundlich adsorption isotherm (x/m) = kp1/n in term of equation of straight ling in intercept form can be written as:

(a) log(x/m) = (1/n) log p+ log k                 (b) log(x/m) = log p + (I/n) log k

(c) log(x/m) = log n+ (I/k) log p (d) log(x/m) = n log p + (1/n) log k

 

  1. The SI units of pre-exponential factor A in equation k = AeEa/RT for zero order reaction are

(a) MS-1                                                (b) M-2S-1

(c) M-1S-1                                              (d) None of these

  1. The phenomenon of scattering of light by colloidal particles is called

(a) Compton Effect                         (b) Doppler Effect

(c) Electrophoresis effect             (d) Tyndall Effect

  1. The units of molal freezing point constant (kT) are

(a) K kg mol-1                                      (b) K kg mol-2

(c) K kg mol                                         (d) K kg-1 mol

  1. The movement of colloidal particles under an applied electric potential is called

(a) Electrophoresis                          (b) Electro-osmosis

(c) Cataphoresis                                               (d) A and C

 

[SUBJECTIVE]

Subject: Chemistry-I (Physical Chemistry)

Time Allowed: 2 Hrs. 45 Min

Maximum Marks: 50

NOTE: ATTEMPT THIS (SUBJECTIVE) ON THE SEPARATE ANSWER SHEET PROVIDED

 

Part-II Give short answers! (20)

Q#1. Define the term solution.

Q#2. What is rate constant? Give units of 1st order rate constant.

Q#3. What is surface tension? Has it any units?

Q#4. Give a mathematical relation between standard Gibbs energy change, enthalpy change and entropy change.

Q#5. What is adsorption?

Q#6. Describe term colloids.

Q#7. Write two properties of colloidal solution.

Q#8. What is main difference between true solution and colloidal solution?

Q#9. Give two applications of adsorption.

Q#10. What do you understand by Gibbs energy?

 

Part-III Questions with brief answers. (30)

Q#3 (a) Discuss heat capacities of gases. (5)

(b) What is Maxwell’s distribution law of molecular velocities? Derive an expression for the most probable velocity using Maxwell’s distribution law. (5)

Q#4 (a) Derive kinetic equation for zero orders reaction. (5)

(b) Briefly describe the purification of colloids. (5)

Q#5 (a) What is adsorption isotherm? Discuss Freundlich’s adsorption isotherm. (5)

(b) Derive Clausius-Clapeyron equation to discuss the effect of temperature on vapor pressure. (5)


[OBJECTIVE]

Subject: Physical Chemistry

Time Allowed: 15 Minutes

Maximum Marks: 10

NOTE: Attempt this Paper on this Question Sheet only. Please encircle the correct option. Division of marks is given in front of each question. This Paper will be collected back after expiry of time limit mentioned above.

 

Part-I Encircle the right answer, cutting and overwriting is not allowed. (10)

  1. Electrolytic conduction differs from metallic conduction from the fict that in the former:

(a) The resistance increases with the increasing temperature.

(b) The resistance decreases with increasing temperature.

(c) The resistance remains constant with increasing temperature.

(d) The resistance is independent of the length of the conductor.

  1. Identify the correct statement regarding fuel cells.

(a) They are more efficient.

(b) They are free from pollution.

(b) They run till the reactants are active.

(d) All of these.

  1. A cell reaction is spontaneous if the cell potential is

(a) Zero

(b) Negative

(c) Positive (d) Infinite

  1. In which of the following the free energy of a chemical reaction is directly converted to electricity.

(a) Lead storage battery

(b) Fuel cell

(c) Concentration cell

(d) Lochlanche cell

  1. When the temperature is raised, the rate of the reaction increases because

(a) Lowering of activation energy

(b) Increase in number of collisions

(c) Decrease in number of active molecules

(d) Decrease in number of collisions

  1. The reaction, 2O2 → 3O2 proceeds in two steps. The rate law for the overall reaction

(a) r = k [O3][O2]

(b) r = k [O3]2

(c) r = k [O3]2[O2]-1

(d) r = k [O3][O2]2

  1. The reaction, 2H2O2 → 2H2O + O2 is a

(a) Zero order reaction

(b) 1st order reaction

(c) 2nd order reaction

(d) 3rd order reaction

  1. Laplacian operator is a

(a) Integral operator

(b) Additional operator

(c) Subtraction operator

(d) Differential operator

  1. The operator “√” is

(a) Linear operator

(b) Diagonal operator

(c) Not linear

(d) Straight line operator

  1. Ψ is symbol used for

(a) Velocity of the wave

(b) amplitude of the wave

(c) Density of the wave

(d) none of the above

[SUBJECTIVE]

Subject: Physical Chemistry

Time Allowed: 2 Hour and 45 Minutes

Maximum Marks: 50

NOTE: ATTEMPT THIS (SUBJECTIVE) ON THE SEPARATE ANSWER SHEET PROVIDED.

 

Part-II Give Short answers, Each question carries equal marks. (20)

Q#1: Explain Arrhenius Factor.

Q#2: Discuss the effect of temperature and concentration on equivalent conductance.

Q#3: Define orthogonality and normalization of wave function?

Q#4: Prove that 1 = u2

Q#5: Justify: the reaction in the solution phase is faster than those in the solid phase?

Q#6: What are Eigen function and Eigen values? Give one example of each.

Q#7: Gives various steps in thermal decomposition of Acetaldehyde and also indicate the rate determining step.

Q#8: Briefly explains Ostwald’s Dilution Law?

Q#9: What is tunnel effect? Give an example?

Q#10: Why Debye-Huckel law is valid only for dilute solution?

 

Part-III Give detailed answers, Each question carries equal marks. (30)

Q#1: (a) Drive a rate expression for 3rd order reaction, when initial concentration of two reactants is same but that of 3rd one is different.

(b) What is parallel reaction? Give its types?

Q#2: (a) Calculate vibrational frequency for Harmonic Oscillator

(b) Give mathematical quantum mechanical description of diatomic rigid states.

Q#3: (a) What is activity coefficient? Determine the activity coefficient for sparingly soluble electrolytes?

(b) Derive an expression of EMF of concentration cell with transference?