BCHCT137 EM 2023 SOLVED ASSIGNMENT

Description

ASSIGNMENT
COORDINATION CHEMISTRY, STATES OF MATTER & CHEMICAL KINETICS
Course Code: BCHCT-137
Assignment Code: BCHCT-137/TMA/2023
Maximum Marks: 100
Note: Attempt all questions. The marks for each question are indicated against it.
PART A: COORDINATION CHEMISTRY
1 a) In potassium which of the two orbitals 3d and 4s has higher energy? Give reasons.
b) Why are high oxidation states stable when we move from the second to the third
row of the transition series?
(3)
(2)
2 In [Ni(H2O)6]
2+ the observed magnetic moment is higher than the spin-only value
explain the reason.
(5)
3 Why do the colours arise in lanthanoid ions and why are the colours pale? (5)
4 What is the definition of a complex? Determine the coordination number and the
oxidation state of the transition metal ion in the [Co(NH3)6]
3+ complex.
(5)
5 What will be the names of the following ligands when they are present in a complex
entity:
CN-
, O2-, Me2As-
, (CH3COCHCOCH3)2 and H2O.
(5)
6 What are the different types of structural isomerism? Give example of any one of
them.
(5)
7 Explain the structure of [MnCl4]
2-
with the help of valence bond theory. (5)
8 Predict the geometry of the Ni(CO)4 complex showing their hybridized orbitals. (5)
9 Calculate the crystal field stabilization energy (CFSE) of an octahedral complex with
four electrons in the d orbitals.
(5)
10 Calculate the spin-only magnetic moment for low-spin octahedral complex of d
5
and d
6
ions. (5)
PART B: STATES OF MATTER & CHEMICAL KINETICS
11 State postulates of kinetic theory of gases and derive the equation: 2
3
1
pV  mNu .
(5)
12 Define mean free path of a molecule. Calculate the mean free path of oxygen molecule at 300
K and 1.013  105
Pa. The collision diameter for the molecule is 1.20  1010 m.
(5)
13 What are critical constants? Derive the relationships between the critical constants
and van der Waals constants.
(5)
14 a) List different factors affecting the rates of chemical reactions.
b) Derive the integrated rate equation for a second order reaction in which a single reactant
forms the product and the reaction rate depends on the second power of the reactant
concentration.
(2)
(3)
15 a) What are clock reactions? What type of rate of reaction is determined by these
reactions?
b) Derive an expression relating the activation energy with the rate constants at two
different temperatures.
(2)
(3)
16 The first-order decomposition of N2O5 is studied at 340 K starting with 2.50 g of
N2O5. If its amount decreases to 1.50 g in 100 s, then calculate:
(5)
4
a) the rate constant
b) the half life of reaction
c) the time required for the amount of N2O5 to reduce to 0.5 g.
17 What are the various intermolecular forces that are responsible for the conversion of
gases into liquids and solids?
(5)
18 Explain with suitable diagrams the planes of symmetry and the axes of symmetry in
the cubic system.
(5)
19 Explain the parameters of a unit cell with the help of a suitable diagram. (5)
20 Tungsten form bcc crystals. Its cell-edge length is 2.18 x10-10. Find the density of
tungsten. (Given: Molar mass of tungsten = 183.84 g per mol).