General Instructions:
- Section A: Q.No. 1 to 16 are MCQs (1 mark each).
- Section B: Q.No. 17 to 21 are VSA (2 marks each).
- Section C: Q.No. 22 to 28 are SA (3 marks each).
- Section D: Q.No. 29 to 30 are Case-based (4 marks each).
- Section E: Q.No. 31 to 33 are LA (5 marks each).
Section A (Multiple Choice)
[1]1. Which of the following is most basic in the
aqueous phase?
A) NH
3 B) (CH
3)
2NH C) (CH
3)
3N
D) CH
3NH
2
Show Answer
B. (CH₃)₂NH (Due to combined inductive and solvation effects).
[1]2. Unit of rate constant for a zero order reaction
is:
A) s
-1 B) L mol
-1s
-1 C) mol L
-1s
-1
D) mol
2L
-2s
-1
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C. mol L⁻¹s⁻¹
[1]3. Identification of primary amines is done by:
A) Lucas test B) Carbylamine test C) Tollens' test D) Iodoform test
Show Answer
B. Carbylamine test.
[1]4. Which of the following is a diamagnetic ion?
A) Sc
3+ B) Ti
3+ C) V
3+ D) Cu
2+
Show Answer
A. Sc³⁺ (No unpaired electrons).
[1]5. In a first order reaction, the time required for
99.9% completion is:
A) 2 times t
1/2 B) 5 times t
1/2 C) 10 times t
1/2
D) 100 times t
1/2
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C. Approx 10 times the half-life.
[1]6. Which sugar is called "Invert Sugar"?
A) Glucose B) Fructose C) Sucrose D) Maltose
Show Answer
C. Sucrose.
[1]7. Correct IUPAC name of
K
3[Fe(CN)
6] is:
A) Potassium hexacyanoiron(III) B) Potassium hexacyanidomeferrate(III) C) Potassium
hexacyanidoferrate(III) D) Hexacyanoferrate potassium
Show Answer
C. Potassium hexacyanidoferrate(III).
[1]8. Lowering of vapour pressure is highest for:
A) 0.1 M Urea B) 0.1 M Glucose C) 0.1 M MgCl
2 D) 0.1 M NaCl
Show Answer
C. MgCl₂ (i=3, highest number of particles).
[1]9. Which of the following is a non-reducing sugar?
A) Glucose B) Lactose C) Maltose D) Sucrose
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D. Sucrose.
[1]10. Primary structure of protein refers to:
A) Helical structure B) Sequence of amino acids C) Three dimensional folding D)
Sub-units
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B. Sequence of amino acids.
[1]11. Lanthanoid contraction is due to:
A) Poor shielding by 4f electrons B) Great shielding by 4f C) High nuclear charge
D) None
Show Answer
A. Poor shielding of 4f electrons.
[1]12. Lucas test is used to distinguish:
A) Amines B) Phenols C) Alcohols D) Acids
Show Answer
C. Alcohols (1°, 2°, 3°).
[1]13. Reaction of RCHO with Fehling's solution gives:
A) Red ppt B) Silver Mirror C) White ppt D) No reaction
Show Answer
A. Red ppt (Cu₂O).
[1]14. Which is an ambidentate ligand?
A) H
2O B) NH
3 C) NO
2- D) Cl
-
Show Answer
C. NO₂⁻ (Can bind via N or O).
[1]15. Coordination number of Co in
[Co(en)
3]
3+ is:
A) 3 B) 6 C) 4 D) 2
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B. 6 (Ethylenediamine is bidentate).
[1]16. Fuel cells convert chemical energy of fuel
into:
A) Heat B) Sound C) Electricity D) Magnetic energy
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C. Electricity.
Section B (VSA - 2 Marks)
[2]17. State Henry’s Law and give its one application.
Show Answer
p = KHx. Application: High altitude (anoxia) or deep sea diving.
[2]18. Why is Cu
2+ colored while
Zn
2+ is colorless?
Show Answer
Cu²⁺ has 3d⁹ configuration (unpaired electron, d-d transition possible). Zn²⁺ has 3d¹⁰
(fully filled, no d-d transition).
[2]19. How do you distinguish between Ethanol and
Methanol?
Show Answer
Iodoform Test: Ethanol gives yellow ppt. Methanol does not.
[2]20. Define Kohlrausch's Law of independent
migration of ions.
Show Answer
Limiting molar conductivity is the sum of individual contributions of cations and
anions.
[2]21. Draw the structure of Zwitterion form of Amino
Glycine.
Show Answer
H₃N⁺-CH₂-COO⁻
Section C (SA - 3 Marks)
[3]22. A first order reaction takes 40 min for 30%
decomposition. Calculate t
1/2.
Show Answer
k = (2.303/40) * log(100/70) = 0.0089 min⁻¹. t½ = 0.693/k = 77.8 min.
[3]23. Explain (a) Hell-Volhard-Zelinsky reaction (b)
Rosenmund reduction.
Show Answer
(a) Alpha-halogenation of acids. (b) Acyl chloride to Aldehyde using H₂/Pd-BaSO₄.
[3]24. Explain the magnetic property and hybridization
of [CoF
6]
3-. (Atomic No. of Co = 27)
Show Answer
Hybridization: sp³d². Outer orbital complex, paramagnetic (High spin).
[3]25. Write the steps of SN1 mechanism with an
example.
Show Answer
Two steps: 1. Carbocation formation 2. Nucleophile attack. Racemization occurs.
[3]26. Why is boiling point of water increased when
salt is added?
(a) Name the property. (b) Calculate the BP of 1M NaCl solution.
Show Answer
(a) Elevation of boiling point (Colligative property). (b) Uses i=2 for NaCl in ΔTb =
i*Kb*m.
[3]27. Give the chemical tests to distinguish: (a)
Propanal and Propanone (b) Phenol and Benzoic acid.
Show Answer
(a) Tollens' test (Propanal gives silver mirror). (b) NaHCO₃ test (Benzoic acid gives
CO₂ effervescence).
[3]28. Account for the following:
(i) p-nitro phenol is more acidic than phenol.
(ii) Methylamine is more basic than ammonia.
Show Answer
(i) -I and -R effect of nitro group stabilizes phenoxide ion. (ii) +I effect of methyl
group increases electron density on N.
Section D (Case Based - 4 Marks)
[4]29. Case Study: Coordination Chemistry.
Werner proposed the concept of primary and secondary valence. In
[Co(NH3)6]Cl3, Co is the central metal.
(i) What is the secondary valence of Co?
(ii) How many moles of AgCl will precipitate with 1 mole of this complex?
Show Answer
(i) 6 (Coordination number). (ii) 3 moles (3 ionizable Cl ions).
[4]30. Case Study: Biomolecules
(Carbohydrates).
Glucose is an aldohexose. On reduction with HI, it gives n-hexane. It exists in alpha and beta forms
called anomers.
(i) What proves the straight chain structure of glucose?
(ii) Define Anomers.
Show Answer
(i) Prolonged heating with HI giving n-hexane. (ii) Diastereomers differing at C1
carbon.
Section E (Long Answer - 5 Marks)
[5]31. (a) Derive the Nernst Equation for a single
electrode.
(b) Calculate E
cell for: Mg | Mg
2+(0.001M) || Cu
2+(0.0001M) | Cu. (E°cell =
2.71 V)
Show Answer
Ecell = E°cell - (0.059/2) * log([Mg²⁺]/[Cu²⁺]) = 2.71 - 0.0295 * log(10) = 2.68 V.
[5]32. (a) Write the chemical reactions for the
following: (i) Reimer-Tiemann (ii) Williamson Synthesis.
(b) How is phenol converted to Aspirin?
Show Answer
(b) Phenol → Salicylic acid (Kolbe's) → Acetylsalicylic acid (Aspirin) via
acetylation.
[5]33. (a) Explain Why: (i)
H
3PO
3 is dibasic. (ii) Noble gases have low boiling points.
(b) Complete the reaction: XeF
4 + H
2O → ?
Show Answer
(a)(i) Contains 2 P-OH bonds. (ii) Weak dispersion forces. (b) Gives Xe + XeO₃ + HF +
O₂.