PART-I a) Complete the following statements by selecting the correct alternative from the

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1 PART-I a) Complete the following statements by selecting the correct alternative from the choices given below: (1 mark each) i. The bond angle in ammonia is: A) 90 o B) 107o C) 109 o D) 120 o ii. The coordination number of hcp crystal is: A) 6 B) l2 C) 14 D) 8 iii. The bond angle in water is: A) 105 o B) 107 o C) 109 o D) 120 o iv. The lowest freezing point of 0.1M aqueous solution is of: A) K 2 SO 4 B) NaCl C) Urea D) Glucose v. Which of the following have zero dipole moment: A) CO 2 B) H 2 O C) SO 2 D) NO 2 vi. There is no hydrogen bonding in : A) acetic acid B) ammonia C) ethanol D) diethyl ether vii. NaCl crystallizes in a fcc lattice, hence the coordination number of sodium chloride salt is : A) 6 B) l2 C) 14 D) 8 viii. An example of intensive property is: A) Number of moles B) Mass C) Volume D) Density

2 ix. To liberate 0.5 mole of hydrogen gas by electrolysis of acidulated water, amount of charge required will be: A) C B) 9650 C C) C D) 0.5 C x. [Co(F 6 )] 3- is: A) A double ion B) Inner orbital complex C) Outer orbital complex D) Low spin complex xi. During an isothermal expansion of an ideal gas: A) Internal energy increases B) Enthalpy decreases C) Enthalpy remains constant D) None of the above xii. Biuret test is given by: A) Urea B) Proteins C) Peptides D) All the above xiii. Hydrolysis of HCN gives: A) Acetic acid. B) Oxalic acid. C) Formic acid D) Formaldehyde xiv. Acetamide is: A) acidic B) basic C) neutral. D) Amphoteric xv. The process employed to extract copper from its ore is: A) Electrolytic reduction. B) Magnetic separation. C) Autoreduction. D) Cyanide process.

3 b) Match the following and write in pairs: (1 mark each) i. Beckmann A) Cryoscopic method ii. Cotrell B) Colligative property iii. Elevation in boiling point C) Ebulloscopic method iv. Isotonic solutions D) V- shaped v. H 2 O E) Pyramidal vi. BeCl 2 F) Same osmotic pressure vii. NH 3 G) Linear viii. Nernst Equation H) Polymer ix. EDTA I) Explosives x. Phenol J) Electrochemical cells xi. Glycerol K) Reimer Tieman reaction xii. Glycol L) Hexadentate c) Fill in the blanks : (1 mark each) i. The in boiling point of a solvent is directly proportional to the of the solution. ii. Boiling point of is more than H 2 S because of iii. iv. In the ammonium ions and bonds are present. The crystal of diamond is made of while that of sodium chloride is made of v. Crystals of and have face centered cubic lattices. vi. The unit cell of sodium chloride has Na + and Cl - ions. vii. Halogens are agents because of their high viii. When a spontaneous reaction takes place, it is accompanied by increase in total of the ix. XeF 4 has geometry and is formed by hybridization. x. Enthalpy is both an and a xi and are functional isomers. xii. FeCl 3 is due to xiii. In the presence of NaCl, the solubility of silver chloride due to xiv. In a galvanic cell the movement of electrons in the external circuit is from to xv. Sodium acetate is due to xvi. Total if the increases, when a spontaneous process takes place.

4 d) Answer the following questions. 1 mark each i. The elevation of boiling point produced by dilute equimolal solutions of three substances are in the order A>glucose>B. Suggest a reason for this observation. ii. Explain the precipitation of silver when copper rod is dipped in silver nitrate solution. iii. Formaldehyde undergoes cannizaro s reaction. Why? iv. Name the type of isomerism exhibited by lactic acid giving reason for your answer. v. How is molar conductivity and specific conductivity related? Give unit of molar conductivity. vi. The osmotic pressure of 0.25 M urea is 2.67 atm. What will be the osmotic pressure of 0.25M potassium sulphate? vii. The aqueous solution of sodium chloride is neutral in nature. Why? viii. A solution X is prepared by dissolving three moles of glucose in one litre of water and solution Y is prepared by dissolving 1.5 moles of sodium chloride in one litre of water. Compare the osmotic pressure of the two solutions and give a reason for your answer. ix. If the ionization constant of acetic acid is k a, what will be the ph of a solution containing equal concentrations of acetic acid and sodium acetate? x. If neutral litmus solution is added to sodium acetate solution, what will you observe and why? xi. Define piezoelectricity and give one use of piezoelectric crystal. PART II Section A a) Phenol associates in water to form a dimmer. A solution of 1.25 g of phenol in 50g water lowered the freezing point by 0.3 o C. what is the degree of association of phenol.( Kf for water is 1.86 K per mol per kg.) b) Show that the time required for the completion of 75% of a reaction of first order is twice the time required for the completion of 50% of the reaction. c) Give reasons for the following: i. Out of aluminium and calcium ions which ion is precipitated from a solution of its salt by NH 4 OH in presence of NH 4 Cl and why? ii. Aqueous solution of copper chloride is acidic in nature. d) Compound lead(ii)sulphide crystallizes in an fcc unit cell. the length of the edge of the unit cell is 500pm. What is the density of the crystal? [ Pb=207.2, S=32] e) When a conductivity cell is filled with 0.02 normal aqueous solution of KCl, the resistance is 350ohm. On filling the same cell with 0.01 normal sodium acetate, the resistance is found to be 1158 ohms. If the specific conductance of 0.02N KCl

5 solution is 27.7 x 10-4 per ohm per cm, calculate the equivalent conductance of sodium acetate solution. f) Calculate the ph at which Mg(OH) 2 begins to precipitate from a solution containing 0.10M magnesium ion. The solubility product of Mg(OH) 2 is 1x g) Compare the crystals of copper and diamond and indicate one similarity and one difference among them. h) For the following cell, calculate the emf: Al/Al 3+ (0.01M)//Fe +2 (0.02M)/Fe Given: E o Al/Al 3+ = V E o Fe +2 /Fe = V i) Explain the following with an example: i. Homogeneous catalysis. ii. Specificity of catalyst. iii. Adsorption theory of catalysis. j) The osmotic pressure of 0.1molar solution of an electrolyte is found to be 0.65atm at 27 o C. Calculate the Vant Hoff factor. What conclusion can you draw about the molecular state of the solute in the solution? k) Two moles of an ideal gas are compressed isothermally and reversibily at 100 o C from a pressure of 10 atm to 25 atm. Find the value of free energy change. l) Give reasons for the following: i. In acid base titration phenolphthalein is used as an indicator. ii. Cu 2+ is precipitated as CuS in acidic medium while Ni 2+ is precipitated as NiS in basic medium with H 2 S. m) Calculate the ph of a buffer solution containing 0.45moles of ammonium hydroxide 0.75 moles of ammonium chloride. The dissociation constant for NH 4 OH is 1.8x10-5 n) For the cell Zn/Zn 2+ (a=1)//cu 2+ /Cu(a=1) Given that E Zn/Zn = volt, E Cu /Cu = volt i. Write the cell reaction. ii. Calculate the emf and free energy change at 298K involved in the cell o) Consider the following reaction: 2Ag + + Cd 2 Ag + Cd 2+ The standard reduction potentials of Ag + / Ag and Cd 2+ / Cd are 0.80volt and volts respectively. i. Give the cell representation. ii. What is the emf of the cell if concentration of Cadmium solution is 0.1M and silver solution is 0.2M? iii. Will the cell work spontaneously for the condition given above. p) i. State Faraday s second law of electrolysis. ii. If the standard free energy change for a reaction is found to be zero, what is the value of the equilibrium constant for the reaction?

6 Section B a) Give the IUPAC names of the following compounds: iii. [Cr(NH 3 ) 5 (CN)][ZnCl 4 ] iv. K[PtCl 3 (NH) 3 ] b) Write the formula of potassiumtrioxalatoferrate(iii). c) Explain the principle involved in the following observations: i. [Ni(CO) 4 ] posses tetrahedral geometry while [Ni(CN) 4 ] 2- is square planar. ii. Square planar complexes do not show optical isomerism. d) Explain the principle involved in the following observations: i. [Fe(CN) 6 ] 3- is paramagnetic while [Fe(CN) 6 ] 4- is diamagnetic. ii. [Ni(Cl 4 )] 2- is paramagnetic while [Ni(CN) 4 ] 2- is diamagnetic. e) Draw the structural isomer of [Co(NH 3 ) 5 NO 2 ]Cl 2 and name the type of isomerism. f) Indicate the steps involved (only the chemical equations) in the extraction of copper from its sulphide ore. g) Write balanced equation for the following reactions: i. Fluorine gas is passed through the dilute solution of sodium hydroxide. ii. Ozone reacts with aqueous solution of potassium iodide. h) Indicate the steps involved in the extraction of fluorine from potassium hydrogen fluoride. i) What is lanthanoid contraction? State its two consequences. j) Account for the following: i. Zinc salts are white while cupric salts are coloured. ii. Interhalogen compounds are strong oxidizing agents. iii. Group 18 elements are less reactive. k) Give reactions and conditions required for the preparation of i. XeF 6 ii. XeOF 4 l) Explain : i. Transition metals form complex compounds. ii. Fluorine shows oxidation state of -1 only while other halogens can show variable oxidation states, m) Give balanced chemical equations: i. Tin is heated with caustic soda solution. ii. Zinc is added to sodium argentocyanide solution. iii. Silver nitrate is added to hypo solution.

7 Section C a) Write balanced equation for the following conversions: i. Acetamide to methyl amine. ii. Methyl amine to ethyl amine. iii. Sucrose is warmed with concentrated nitric acid. b) How would you convert: i. Glucose to fructose. ii. Glucose to gluconic acid. c) How will you distinguish primary, secondary and tertiary amine using nitrous acid ( NaNO 2 + dil HCl) or any other test. a) i. Why is meso tartaric acid optically active. ii.name the monomers of Teflon and Bakellite. b)what are the reaction products of the following: HNO 3 /H 2 SO 4 Br 2 / Fe A B Br 2 / Fe C HNO 3 /H 2 SO D Why same compounds are not obtained in the final stage? c) How is phenol prepared from chlorobenzene? Give all conditions. a) Give reasons in support of amphoteric nature of glycine. Mention the ph of isoelectric point. b) Distinguish between acetone and acetic acid. c) What is the compound formed when chlorine is bubbled through boiling acetic acid for a short time in presence of iodine? Name the compound formed when the above compound is treated with concentrated solution of ammonia. d) How would you convert: i. Acetic acid to methane ii. Oxalic acid to formic acid. e) Give balanced equations for: i. Acetic acid with PCl5

8 ii. Urea is heated. a) Give balanced equations for the following reactions: i. Benzoylation of aniline. ii. Benzoic acid is treated with sodium carbonate. iii. Wohler s synthesis to prepare urea. b) i. At 110 o C oxalic acid reacts with an organic compound A having molecular formula C 3 H 8 O 3 to yield a monocarboxylic acid B. B gives silver mirror test with Tollen s reagent and reduces acidified potassium permanganate solution. Identify A and B. ii. Draw the structures of three isomers which have the molecular formula C 3 H 8 O and write their names. c) i. What is the denaturation of proteins? ii. Write the chemical names and deficiency diseases of the following vitamins. 1. Vitamin A 2. Vitamin B 3. Vitamin D 4. Vitamin K a) i. Give equations for the reduction of Nitrobenzene both in acidic and neutral medium. ii. Give equations for the conversion of Benzoic acid to Benzene and vice versa. iii. Give balanced equation for the reaction between aniline and bromine water. Give your observations. b) Give balanced equations for the following reactions: i. Benzaldehyde and hydroxyl amine. ii. Benzoic acid and phosphorous penta chloride. aldehydes. c) How do you distinguish between aromatic aldehydes and aliphatic d) An organic compound A with molecular formula C 2 H 7 N give a compound B on reaction with nitrous acid. On controlled oxidation B gives a compound C. C reduces Tollen s reagent to give silver mirror and a compound D. in the presence of concentrated sulphuric acid B reacts with D to give a sweet smelling compound E. Identify A, B, C, D and E. Give the reaction of C with ammonia and name the product. a) Give balanced equations for the following reactions:

9 i. Cannizaro s reaction. ii. Gattermann reaction. iii. Carbyl amine reaction. b) i. What is specific roatation? ii. What is optical activity? Name the instrument used to measure the optical activity. Mention two necessary conditions for a compound to show optical activity. Give one example of compound which shows optical activity. c) i. What are thermosetting and thermoplastics? Mention an example of each. ii. Mention the monomers of Bakelite. What is the type of polymerization in Bakelite? iii. Give balanced equation between urea and sodium hydroxide. Give the names of the following reactions: i. C 2 H 5 Br + C 2 H 5 ONa C 2 H 5 O C 2 H 5 + NaBr OH - ii. CH 3 CHO + CH 3 CO CH CH 3 CH(OH) CH 2 CO CH 3 a) Identify the products PCl 5 NH 3 NaOH CH 3 COOH A B C +D b) Identify the reagents A B C Benzene Nitrobenzene Aniline Aniline hydrochloride D Benzene diazonium chloride b) A n organic compound A with molecular formula C 2 H 7 N give a compound B on reaction with nitrous acid. On controlled oxidation B gives a compound C. C reduces Tollen s reagent to give silver mirror and a compound D. in the presence of concentrated sulphuric acid B reacts with D to give a sweet smelling compound E. Identify A, B, C, D and E. give the reaction of C with ammonia and name the product. c) i. Distinguish between primary, secondary and tertiary amines using Hinsberg s reagent. ii. Arrange the following in correct basic order. Ammonia, Primary amine, secondary amine and tertiary amine. iii. Give equation for Hoffmann Bromamide reaction a) i. Aniline cannot be nitrated directly. Why? i. What are the products formed when phenol and nitrobenzene are treated with a mixture of conc sulphuric acid and conc nitric acid.

10 ii. How would you convert methylamine to ethyl amine. Give equations. b) i. what happens when methyl isocyanide is warmed with dilute hydrochloric acid. ii. Which is most basic: a) C 6 H 5 NH 2 b) (C 6 H 5 ) 2 NH c) (CH 3 ) 2 NH d) CH 3 NH 2 c) Give the names and formulae of A, B, C, D, E and F in the following reactions: [A] conc HNO 3 /conc H 2 SO 4 [B] Sn/HCl, heat [C] CHCl 3 /KOH [D] H 2 /Pt [E] [F] NHCOCH 3 + HCl How will you distinguish between: i. Ethyl cyanide and ethyl isocyanide. ii. Aniline and dimethyl aniline. iii. Acetophenone and benzophenone. iv. Ethyl amine and acetamide.

CHEMISTRY PAPER 1 (THEORY)

Question 1 (a) For more sample papers visit : www.4ono.com CHEMISTRY PAPER 1 (THEORY) (Three Hours) (Candidates are allowed additional 15 minutes for only reading the paper. They must NOT start writing