IGNOU BCHCT-137 June 2022 Previous Year Question Paper

Q1.What are the electronic configurations of K, Ca and Sc ? Predict the ground state configuration of Sc* ion.

Q2.Which of the following ions is colourless and why? 5

(a) Ni?

(b) Fe3*

Q3.Why is the chemistry of actinoids much more complicated than that of lanthanoids ?

Q4.What are ambidentate ligands ? Give suitable examples and name them using the K-convention.

Q5.Give the different types of structural isomerism in metal complexes.

Q6.Explain the crystal field effects in weak and strong fields with the help of a d* complex.

Q7.Compare the Crystal Field Stabilisation Energies (CFSE) for octahedral and tetrahedral metal complexes with suitable examples. 5 BCHCT-137 2 PARTB (Maximum Marks : 25)

Q8.(a) One mole of oxygen gas occupied a volume of 0-025 m® at 27°C. If the gas behaves ideally, calculate the pressure of the gas. 2

(b) Derive the ideal gas equation from the following expression for pressure of a gas. 3 P= 1 mNu 3 OV

Q9.(a) Give the two assumptions of kinetic theory of gases that are not valid for real gases. 2

(b) The Van der Waal’s constants for ammonia gas are as follows : a = 0-4225 Pa m® mol; b = 37-07 x 106 m3 mol? Calculate the values for critical constants for ammonia gas.

Q10.What is meant by viscosity of a liquid ? Why is the viscosity of water at 373 K one-sixth of its viscosity at 273 K ?

Q11.Define lattice and basis in context of crystal systems and illustrate them with suitable diagrams.

Q12.Explain the concept of packing efficiency in a simple cubic lattice.

Q13.(a) Define order of a reaction. 2

(b) For the following reaction, the half-life is found to be inversely proportional to the initial concentration of A. A = Products

(i) What is the order of the reaction ?

(ii) If half-life of the reaction is 30 s, how long would it take for the concentration to reduce to 6:25% of the initial value ?

Q14.The following reaction was studied by initial rate method : Cly

(g) + NO

(g) ——> 2NOCI

(g) The initial rates of different concentrations of Cl, and NO were determined and are given below : [Cl./M [NO|/M Initial rate/Ms~! 0-10 0-10 3x 10% 0-20 0-10 6x 10% 0-20 0-20 24x10? Calculate : 5

(a) Order of the reaction with respect to Clg and NO

(b) Overall order of reaction

(c) Rate constant BCHCT-137 4

(क) Niz+ BCHCT-137 6 pal mNu? 3 OV a = 0-4225 Pa m® mol; b = 37-07 x 10-6 m? mol Cly

(g) + NO

(g) ——> 2NOCI|

(g) [Cly]/M [NOM — anf qyMs-! 0-10 0-10 3x 10% 0-20 0-10 6x 10% 0-20 0-20 2-4 x 10°?