CHEMSITRY
150 MARKS
Lessons:1to10
1 Marks
1. Which of the following particle having same kinetic energy, would have the
maximum de-Broglie wave length
a) -particle b) proton c) -particle d) neutron
2. If the energy of an electron in the second Bohr orbit of H-atom is -E, what
is the energy of the electron in the Bohr’s first orbit?
a) 2E b) -4E c) -2E d) 4E
3. The bond order of oxygen molecule is
a) 2.5 b) 1 c) 3 d) 2
4. The value of C-C distance found experimentally in a saturated hydrocarbon
is
a) 1.34Å b) 1.36Å c) 1.54Å d) 1.56Å
5. On moving down the group, the radius of an ion
a) Decreases b) Increases c) No change d)None of these
6. Effective nuclear charge (Z*) can be calculated by using the formula
a) Z* = Z – S b) Z* = Z + S c) Z* = S – Z d) Z = Z* – S
7. Which of the following does not belong to group 13?
a) B b) Al c) Ge d) In
8. Which of the following is most abundant in earth’s crust?
a) C b) Si c) Ge d) Sn
9. An element which was burnt in limited supply of air to give oxide A which
on treatment with water gives an acid. B. Acid B on heating gives acid C
which gives yellow precipitate with AgNO3 solution A is
a) SO2 b) NO2 c) P2 O3 d) SO3
10) Formation of coloured ions is possible when compounds contains
a) paired electrons b) unpaired electrons
c) lone pairs of electrons d) none of the above
11). Paramagnetism is common in
a) p-block elements b) d-block elements
c) s-block elements d) f-block elements
12). The colour of Ti(H2O)63+ ion is due
a) d-d transistion
b) Presence of water molecules
c) Inter atomic transfer of electrons
d) None of the above
13) The lanthanide contraction is responsible for the fact that
a) Zn and Y have about the same radius
b) Zr and Nb have similar oxidation state
1X30=30
c) Zr and Hf have about the same radius
d) Zr and Zn have the same oxidation state
14. The most common oxidation state of lanthanides is
a) +2 b) +1 c) +3 d) +4
15. Lanthanides are extracted from
a) Limonite b) Monazite c) Magnetite d) Cassiterite
16. The geometry of [Cu(NH3)4]2+ complex ion
a) Linear b) Tetrahedral c) Square planar d) Angular
17. An example of a chelating ligand is
a) NO-2 b) Chloro c) Bromo d) en
18. The geometry of complex ion [Fe(CN)6]4- is
a) tetrahedral b) square planar c) Octahedral d) triangular
19. Radioactivity is due to
a) Stable electronic configuration b) Stable nucleus
c) Unstable nucleus d) Unstable electronic configuration
20. Which of the following is used as neutron absorber in the nuclear reactor?
a) Water b) Deuterium c) Some compound of uranium d) Cadmium
21. The number of chloride ions that surrounds the central Na+ ion in NaCl
crystal is_______.
(a) 12 (b) 8 (c) 6 (d) 4
22. A regular three dimensional arrangement of identical points in space is called
(a) Unit cell (b) Space lattice (c) Primitive (d) Crystallography
23. The smallest repeating unit in space lattice which when repeated over and
again results in the crystal of the given substance is called
(a) Space lattice (b) Crystal lattice (c)Unit cell (d) Isomorphism
24. The crystal structure of CsCl is
(a) Simple cubic (b) face-centred cubic
(c) Tetragonal (d) Body centred cubic
25. All the naturally occuring processes proceed spontaneously in a direction
which leads to
a) decrease of entropy b) increase in enthalpy
c) increase in free energy d) decrease of free energy
26. State of chemical equilibrium is:
a) dynamic b) stationery c) none d) both
27. Two moles of ammonia gas are introduced into a previously evacuated 1.0
dm3 vessel in which it partially dissociates at high temperature. At equilibrium
1.0 mole of ammonia remains. The equilibrium constant Kc for the dissociation
is
a) 27/16 (mole dm-3)2 b) 27/8 (mole dm-3)2
c) 27/4 (mole dm-3)2 c) None of these
28. An equilibrium reaction is endothermic if K1 and K2 are the equilibrium
constants at T1 and T2 temperatures respectively and if T2 is greater than T1
then
a) K1 is less than K2 b) K1 is greater than K2
c) K1 is equal to K2 d) None
29. Paramagnetic moment is expressed in
a) Debye unit b) K Joules c) BM d) ergs
30. Valence bond theory does not explain the property of complex compound
a) geometry b) magnetic c) nature of ligand d) colour
3 Marks
3X15=45
1.
2.
3.
4.
5.
What are molecular orbitals.
Why is He2 not formed?
Mention the disadvantage of pauling and mulliken scale.
why is the electron affinity of fluorine less than that of chlorine?
The electron energy of hydrogen atom in the ground state works out to be
–2.18 10-18 J per atom. Calculate what will happen to the position of the
electron in this atom if an energy of 1.938 10-18J is supplied to the each hydrogen
atom.
6. Distinguish electron affinity and electronegativity.
7. prove that P2O5 is a powerful dehydrating agent.
8. Explain why d-block elements exhibit variable oxidation states.
9. What is the action of heat on copper sulpate crystals?
10. .Explain why Mn2+ is more stable than Mn3+?
11. What are mish metals?Give their uses.
12. What are ligands and coordination numbers?
13. The diffraction of crystal of Barium with X-ray of wavelength 2.29A° gives
14. a first order reflection at 27°8. What is the distance between the diffracted
planes?
15. What is Q value of a nuclear reaction?
16. State Bragg’s law.
17. The half-life of cobalt - 60 is 5.26 years. Calculate the % activity remaining
after 4 years.
18. Give Kelvin statement of second law of thermodynamics.
19. .Degree of dissociation of PCl5 at 1 atm and 25C is 0.2. Calculate the
pressure at which PCl5 is half dissociated at 25C.
20. Define reaction quotient.
5 Marks
7X5 =35
1.
Explain briefly the extraction of copper from its chief ore.
2.Name the ores of gold .Explain how it is extracted from its alluvial gravel.
3. Separation of noble gases (Dewar’s method)
4. Explain the schottky and frenkel defect?
5. Calculate the number of and β particles emitted in the conversion of
90Th 232 to 82pb208
6. The geometry of the molecule is octahedral
1) Fe atom 2) Fe+2 ion
7. Extraction of lanthanide from monazite sand
8. Explain the Characteristics of entropy ‘S’.
9. Initially, 0.1 moles each of H2 and I2 gases and 0.02 moles of HI gas
are mixed in a reaction vessel of constant volume at 300K. Predict the direction
towards which the reaction proceeds [Kc = 3.5 × 10-2].
10. Explain the Silicones – structure and uses
10 Marks
4 X10 =40
1.a) Molecular orbital energy level diagram of O2 molecule
b) Calculate the electronegativity values of fluorine and chlorine on Mulliken’s
scale, given that (Ionisation potential) F = 17.4 eV/atom (Electron affinity) F =
3.62 ev/atom, (IP)Cl = 13.0 ev/atom and (EA)Cl = 4.0 ev
2.a)Explain the Applications of electronegativity.
b) Comparison of Lanthanides and Actinides
3) Coordination compounds exhibit two major types of isomerism, namely
structural isomerism
a)Coordination isomerism b) Ionisation isomerism
c) Hydrate or Solvate isomerism d) Linkage isomerism
e) Ligand Isomerism
4) Explain the applications of colloid chemistry are limitless. These can be divided
mainly into two classes:
1. Natural applications and
2. Technical applications
5.a) The activation energy of a certain reaction is 100 KJ/mole
what is the change in the rate constant of the reaction if the temperature is
changed from 25°C to 35°C ? Let the rate constants at 25°C be k1 and at
35°C be k2 respectively.
b) Explain the Characteristics of Free energy ‘G’.
6.a) Preparation of potassium dichromate from chrome iron ore
b) ) IUPAC NOMENCLATURE OF MONONUCLEAR
COORDINATION COMPOUNDS
The rules are outlined below
7 a) Calculate the entropy changes in the system, and in the surroundings and
the total entropy change in the universe when during a process 75 J of heat flow
out of the system at 55oC to the surroundings at 20oC.
b) Explain the Haber’s Process.