IIT-JEE 2012 PAPER - 1 PART - II : CHEMISTRY. SECTION - I : Single Correct Answer Type

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1 IIT-JEE 0 PAPER - PART - II : CHEMISTRY SECTION - I : Single Correct Answer Type Tis section contains 0 multiple coice questions, Eac question as four coices, (A), (B), (C) and (D) out of wic ONLY ONE is correct.. Wic ordering of compounds is according to te decreasing order of te oxidation state of nitrogen? (A) HNO 3, NO, NH 4 Cl, N (B) HNO 3, NO, N, NH 4 Cl (C) HNO 3, NH 4 Cl, NO, N (D) NO, HNO 3, NH 4 Cl, N (B) HNO 3 = + 5 NO = + NH 4 Cl = 3 N = 0 So correct order will be HNO 3, NO, N, NH 4 Cl.. Te kinetic energy of an electron in te second Bor orbit of a ydrogen atom is [a 0 is Bor radius] : (A) 4 ma 0 (B) 6 ma 0 (C) 3 ma 0 (D) 64 ma 0 (C) mv (4a 0 ) = so, v = 4m a 0 so KE = mv = m. 6m a 0 = 3m a 0 Page #

2 3. Te number of aldol reaction (s) tat occurs in te given transformation is : CH 3 CHO + 4HCHO conc. aq. NaOH (A) (B) (C) 3 (D) 4 (C) CH 3 CHO + HCHO OH OH /HCHO st aldol ndaldol condensation condensation OH /HCHO 3rd aldol condensation 4. For one mole of a van der Waals gas wen b = 0 and T = 300 K, te PV vs./v plot is sown below. Te value of te van der Waals constant a (atm.liter mol ) : (A).0 (B) 4.5 (C).5 (D) 3.0 (C) Page #

3 a P (V) = RT V PV + a/v = RT PV = RT a(v) y = RT a(x) So slope = a = =.5 =.5 5. In allene (C 3 H 4 ), te type(s) of ybridisation of te carbon atoms is (are) : (A) sp and sp 3 (B) sp and sp (C) only sp 3 (D) sp and sp 3 (B) C 3 H 4 6. A compound M P X q as cubic close packing (ccp) arrangement of X. Its unit cell structure is sown below. Te empirical formula of te compound is (A) MX (B) MX (C) M X (D) M 5 X 4 (B) No. of M atoms = = + = No. of X atoms = = 3 + = 4 so formula = M X 4 = MX Page # 3

4 7. Te number of optically active products obtained from te complete ozonolysis of te given compound is: (A) 0 (B) (C) (D) 4 (A) O / Zn/H O 3 CH 3 CHO + CH3 CH CHO CHO All optically inactive products 8. As per IUPAC nomenclature, te name of te complex [Co(H O) 4 (NH 3 ) ]Cl 3 is : (A) Tetraaquadiaminecobalt (III) cloride (C) Diaminetetraaquacoblat (III) cloride (D) [Co(H O) 4 (NH 3 ) ]Cl 3 = Diamminetetraaquacobalt (III) cloride. (B) Tetraaquadiamminecobalt (III) cloride (D) Diamminetetraaquacobalt (III) cloride 9. Te carboxyl functional group ( COOH) is present in (A) picric acid (B) barbituric acid (C) ascorbic acid (D) aspirin (D) Sol. picric acid ; barbituric acid ascorbic acid ; aspirin Page # 4

5 30. Te colour of ligt absorbed by an aqueous solution of CuSO 4 is : (A) organge-red (B) blue-green (C) yellow (D) violet (A) CuSO 4 will be absorbing orange-red colour & ence will be of blue colour. CHEMISTRY SECTION II : Multiple Correct Answer(s) Type Tis section contains 5 multiple coice questions. Eac question as four coices (A), (B), (C) and (D) out of wic ONE or MORE are correct. 3. For an ideal gas, consider only P-V work in going from an initial state X to te final stat Z. Te final state Z can be reaced by eiter of te two pats sown in te figure. Wic of te following coice(s) is (are) correct? [take S as cange in entropy and w as work done]. (A) S xz =S xy + S yz (B) w xz = w xy + w yz (C) w xzz = w xy (D) S xyz =S xy (AC) (A) S xz = S x y + S yz (B) W xy = W x y + W yz (C) W xyz = W x y (D) S xyz = S x y (Correct) (Incorrect) (Correct) (Incorrect) 3. Wic of te following molecules, in pure form, is (are) unstable at room temperature? (A) (B) (C) (D) (B) is antiaromatic and unstable Page # 5

6 33. Identify te binary mixture(s) tat can be separated into individual compounds, by differential extraction, as sown in te given sceme. (A) C 6 OH and C 6 COOH (C) C 6 OH and C 6 OH (BD) (B) C 6 COOH and C 6 OH (D) C 6 OH and C 6 COOH (B) C 6 COOH + C 6 OH aq. NaOH (soluble) + (insoluble) (soluble) + (insoluble) (D) C 3 OH + C 6 COOH aq. NaOH (insoluble) + (soluble) () (insoluble) + (soluble). 34. Coose te correct reason(s) for te stability of te lyopobic colloidal particles. (A) Preferential adsorption of ions on teir surface from te solution. (B) Preferential adsorption of solvent on teir surface from te solution. (C) Attraction between different particles aving opposite carges on teir surface. (D) Potential difference between te fixed layer and te diffused layer of opposite carges around te colloidal particles. (AD) (A) due to preferential adsorption of common ions (B) X (C) X (due to repulsion not due to attraction) (D) Te layer of oppositely carged particles around any colloidal particles will decrease te potential energy of system as a wole. 35. Wic of te following alides react(s) wit AgNO 3 (aq) to give a precipitate tat dissolves in Na S O 3 (aq)? (A) HCl (B) HF (C) HBr (D) HI (ACD) AgNO + HCl AgCl AgNO 3 + HBr AgBr AgNO 3 + HI Ag All tese precipitates will get dissolved in ypo forming complex Na 3 [Ag(S O 3 ) ] Page # 6

7 SECTION - III : Integer Answer Type Tis section contains 5 questions. Te answer to eac question is a single-digit integer, ranging from 0 to 9 (bot inclusive). 36. An organic compound undergoes first-order decomposition. Te time taken for its decomposition to /8 and 9 [t / 8 ] /0 of its initial concentration are t /8 and t /0 respectively. Wat is te value of 0?(log [t ] 0 = 0.3) /0 CO Kt /8 = In CO / 8 = In 8 CO Kt /0 = In CO /0 = In 0 t/ 8 In 8 log ten 0 t = 0 = 0 = 9 In 0 log 0 /0 37. Wen te following aldoexose exists in its D-configuration, te total number of stereoisomers in its pyranose form is : 8 Total stereoisomers = 3 = 8 Page # 7

8 38. Te substituents R and R for nine peptides are listed in te table given below. How many of tese peptides are positively carged at ph = 7.0? 4 Peptide R R I H H II H CH 3 III COOH H IV CONH ( ) 4 NH V CONH CONH VI ( ) 4 NH ( ) 4 NH VII COOH CONH VIII OH ( ) 4 NH IX ( ) 4 NH CH 3 For te polypeptide te isoelectric point will be more tan 7. Tat means te given polypeptide is of basic nature so it must contain two or more amino groups. So (iv), (vi), (viii) and (ix) are te correct options. 39. Te periodic table consists of 8 groups. An isotope of copper, on bombardment wit protons, undergoes a nuclear reaction yielding element X as sown below. To wic group, element X belongs in te periodic table? C H 6 n H X 63 9Cu H 60n H X 4 64 = A A = = 30 = z z = 6 element X sould be iron in group % (w/w) HCl stock solution as a density of.5 g ml. Te molecular weigt of HCl is 36.5 g mol. Te volume (ml) of stock solution required to prepare a 00 ml solution of 0.4 M HCl is : 8 9.% (w/w) HCl as density =.5 g/ml Now, mole of HCl required in 0.4 M HCl = mole = 0.08 mole if v mol of orginal HCl solution is taken ten mass of solution =.5 v mass of HCl = (.5 v 0.9) mole of HCl =.5v = 0.08 so, v = mol = 8 ml Page # 8