BSC Chemistry Part-II Semester-III Exam Paper PDF

https://www.sgbauonline.com AW-1685 B.Sc. (Part-II) Scmcstcr-IIl Eramination CTIENIISTRY Time...

https://www.sgbauonline.com AW-1685 B.Sc. (Part-II) Scmcstcr-IIl Eramination CTIENIISTRY Time : Three lloLrrsl [Maximum Marks : 80 Notc r-(l) Quesrion No. I is compulsory. (2) Solve ONE question from each unit. (3) Draw diagrams and give equations wherever necessary. (4) Use of scientific calculator is allowed. 1. (A) Fill in the blanks :- 4x1A=2 (i) Thc property of metals 10 form thin shccts on hamrnering is known as _. (iD LiAIU! reduccs the carbonyl group into group. (iii) Thc surface tensioo of liquid wilh increase of the temperature. (iv) 'l hc titration betwecn an acid and the base is also called as _. (B) Choose the comect altemative :- 4xy,=2 (i) In contbrmational analysis of n-butanc thc highly stable conformation is : (a) Gauchc (b) Anti or Skew (c) Pa ially Eclipsed (d) Fully Eclipsed (ii) 1hc hybridisation of carbon and oxygen atoms in carbonyl group is : (a) sp' (b) sp (c) sp' (d) dsp'z (iii) l'he critical solution tcmpcrature of Phenol-watff system is : 'rppcr (a) 68.1 (b) 67.8 (c) 68.7 (d) 67.9 (iv) In gravimetric estimation the unknown compound is analysed by mcasuring ils : (a) Prcssure (b) Volumc (c) Density (d) lvlass (C) Answer the follorving in ONE scntcnco :- 4 (i) What is meart by rcsohrtion'1 (ii) What is phase transition ? (iii) What are optically active. compounds ? (iv) What is molality ? UNIT-I 2. (A) Explain VSEPR theory rvith suitable example. 4 (B) tlow rvill )ou compare atomic orbitals \rith molecular orbitals ? 4 (C) l)raw molccular orbital energy lcvel diagram ofO, molecule. Calculate its bond order. 4 OR Yitc-15256 (Contd.) https://www.sgbauonline.com 3 (P) Ilow will you dift'crentiat. bonding and antibonding molecular orbitals ? 4 (Q) Discuss (i) metalic luster (ii) lllectrical conductivily of metal on the basis of frce electron tl"eory. 4 (R) Discuss thc structure of BF. rnolecule on the basis of VSEPR theory 4 I,INTT-II.1 (A) Calculate the mole fraction of ethanol and \\'atcr, if solution contains 6 moles of ethanol and 3 moles of \r':rter 4 (B) Explain the terms :--. (i) Normality (ii) Molality. 4 (C) Discuss lhc choice of suitrblc indicator in srrong acid uirh weak base. 4 OR (P) Discuss the follouing steps in\olved in gralimelric estimation of Barium as barium Sulphatc: (i) I'rccipitation (ii) Digcstion. 4 (q; Wrltc a n(rtc on Iodimetry and Iodometry. 4 (R) Explain :-- (i) End I'oint (ii) Molarity. 4 UNIT-III 6 (A) Complete the follo\\'ine rescrior)( : (i) (lllr {lH, OH + lol K.CrrOT ,, - ,, II' oo 1l (ii) H-c-lJ + H-c-H l1 str% NaoH.-?r?.l (B) How will you preparc acetonc fti,m : (i) lsopropyl alcohol (ii) 2, 2-t)ichloro propane 'l.l (C) What happens when Benzcic acid is trcatcd with (i) Ethyl alcohol in presence of conc. H,SO. (ii) PCl, io presence of conc. H,SO. ?.l OR YBC 15256 (Conld.) https://www.sgbauonline.com 7 (P) llow will you prepare Benzoic acid from (i) I3cnzyt alcohol (ii) Phenvl cyanide. 4 (Q) What happens *hcn (i) Ethylcne glycol on oxidation with chromic acid (ii) Lactic acid reacts with cthanol in conc. H,SO, ? 4 (R) Explain Aldol coodensation in Aldehydes and Ketones with example. 4 UNIT-IV 8 (A) Explain thc lollowing : (i) Plane of symmctry (ii) Ccntrc of symmetry. 4 (B) Assign thc following groups in propcr priority order according to 'R' and 'S' nomenclature system : (D -COOH, - , -CHl -NHr, (ii) --{H' -H' -cH3 4 -c1H5' (C) What is geometrical isomerism ? Explain with suitablc cxample. 4 OR 9 (P) Explain the conformalional analysis of n-butaIle with encrgy lcvel diagram. 4 (Q) Explain the tcrms : (i) Chirality (ii) Racemisation. 4 (R) Classify thc lbllowing compounds into E-2 t)?e : Ilr CI CH. CII, cHl-cH' /H /H ICH.. c C tl C (l C =ctH c r I CII CI CI t,' CII clls 4 UNIT_V 10. (A) Explain the variation of Cibbs frcc energy u'ith tempcrature and pressuc. 4 (B) State and cxplain Ncrst Distribution Law. State the conditions of its validity 4 (C) What is exlraction ? Explain its lypcs. 4 OR I l. (P) Derivc Gibb's-Duhem equatioo. 4 (Q) Explain the Phenol-Watcr system. 4 YBC-r 5256 3 (Conrd.) https://www.sgbauonline.com (R) The Valuc of Kp for \Ihtcr gas rcaction CO(g) 1 tl,O(g) :- CO.(g) | tl1(g) is 1.6 x l(r at 25"C. Calculate the standard licc crergl'changc (AC') of the re3ction ar 25"C. (R = 8.314 JK-' mole ) 4 LNIT-\'I rz. tel How rclative viscosity ol liquirl is dctermincd by Ostuald's Viscometer ? 1 (B) l)efine :- (i) Ccll constant (ii) Molar conduclancc. I (c) 0.5 N solution of salt ()ccupl-ing volumc betur'en trro platinum elcctrodes 0.0172 m apafi and 0.04499 sq m. ar,:a has rcsistancc 2j ohm. Calculate equivalent conduclancc of solution. 4 OR 13. (P) What arc thc advantages of corrdLrctomclric lilrations ovcr ordinary titrations ? 4 (a) Explain thr: varialion ol sriccilic and equivalcnt conductancc with diluiion. 4 (R) l)cscribe moving boundar] mcthod lbr dcl.ymination of transport number. 4 YBC-15256 625