CAREER POINT. CENTRAL BOARD OF SENIOR SECONDARY EXAMINATION CHEMISTRY (Theory) SOLUTIONS

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1 CAREER PINT MCK TEST PAPER CENTRAL BARD SENI SECNDARY EXAMINATIN CHEMISTRY (Theory) SLUTINS Sol. 1 Negative deviatio Sol. 9 (a) p-type, because I has 3 valece electros. Holes are produced which ca Sol. e 3 is a better coagulatig io due to greater positive charge o itmove through the crystal like positive charge. (b) -type, because P has 5 valece electros. Sol. 3 sucrose H Glucose fructose The fifth electro becomes delocalised ad is free cotribute to electrical Sol. 4 Due to the formatio of [P 4 ] [P 6 ] coductio. Sol. 5 Sol. 6 cresol, ailie H S 4 caot be used alog with KI i the coversio of a alcohol to a alkyl iodide as it coverts KI to correspodig HI ad the oxidieses it to I. Sol. 10 Aode Cathode ( ) () H Na or K Sol. 7 Sol. 8 CH Cumee C H Cumee Hydroperoxide H H 1-Pheyl peta-1-oe CH CH CH C C Porous carbo electrode impregated with Pt At aode at high pressure H is supplied ad followig chemical reactio takes place At Aode : H (g) (aq) H (l) e At cathode at pressure oxyge is supplied ad followig reactio takes place 1 (g) H( l ) e (aq) Cell reactio : 1 (g) (g) H (l) H CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # 1

2 Coductig ca be defied as the tedecy of the solutio to coduct electricity ad coductace of all the ios preset i 1 cm 3 of solutio which is preset betwee electrodes preset 1 cm apart ad area of electrode is such that whole solutio is preset betwee them- Molar coductig ca be defied as coductace of all the ios preset i V cm 3 of solutio cotaiig 1 mol electrolyte ad solutio is kept betwee electrodes preset 1 cm apart ad area of electrode is such that it cotai whole solutio betwee them uits of specific coductivity K S cm 1 molar coductivity Λ m Scm mol 1 Sol. 11 Give W A 19.5 g, W B 500g, K f 1.86 Kgmol 1 ΔT f (obs) 1 C Kf WB 1000 Δ Tf M M M B B f A K f WB 1000 ΔT M A K kg mol 19.5g 1000g 1.0K 500kg 7.54 gmol 1 Molecular mass of CH C g mol 1 i ormal molecular mass/observed molecular mass 78/ CH C CH C H C mol L C(1 α) Cα Cα a i k a [CHC ][H [CH C] C 0.5M K a Cα ] Cα Cα C(1 α) 1 α K a 0.5 (0.0753) K a Sol. 1 (a) Due to the formatio of chemical bods betwee adsorbate ad adsorbet i case of chemisorptios (b) Browia movemet ad Tydall effect (c) The movemet of colloidal particles uder a applied electrical potetial is electrophoresis. Whe electrophoresis of dispersed particle i a colloidal system is preveted by some suitable meas, it is observed that dispersio medium itself begis to move i a electric field. This pheomeo is kow as electro osmosis. Sol. 13 No. of moles of ethylee glycol B Molar mass of C H 6 (4 6 3)g mol 1 g NB 3.58 mol 1 6mol mass of solutio (50 )g 47g Sol. 14 (a) As flux to remove e impurities i the form of slag esi 3. (b) Roastig :- Heatig of ore i excess of air below its meltig poit Calciatios :- Heatig of ore i limited supply of air below its meltig poit Sol. 15 (a) CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # S (b) Xe Sol. 16 (a) Due to strog iter particle force (b) Due to variable oxidatio state Sol. 17 I gaseous phase, basic character of amies icreases with icreases i umber of electro releasig groups, due to I effect, so tred of basic character is 3 > > 1.

3 But i aqueous phase, salvatio of ammoium catio occurs by water molecules, greater the size of io, lesser will be the salvatio, ad lesser will be the stability of io, so o combiig I effect ad salvatio effect, i aqueous phase tred chages to > 3 > 1. Sol. 18 (a) Durig riedel Craft's alkylatio, alumiium chloride acts as a catalyst, as well as a Lewis acid, if forms salt with NH group of ailie, so that NH group acquires a positive charge, ad acts as a deactivatig group, so ailie does ot udergo CA. (b) Durig itratio i strogly acidic medium ailie is protoated to form ailiium io, which is a meta directig group, so alog with o & p isomers, meta isomers is also obtaied. Sol. 19 (a) I the first cell silver is deposited at cathode accordig to the equatio (i) Ag (aq) e Ag (s) gag 1 electricity 1. 78gAg C electricity (ii) The oxyge gas is liberated at aode of first cell as well as secod cell accordig to equatio H ( l ) 4H (aq) 4e (g) 4 Electricity 1 mol i each cell 4 3g i each cell 3g g 4g 0.08 g i each cell Total weight of liberated 0.08g 0.16 g (i both cells) (b) (i) The equilibrium costat 0 K ad E are related by the relatio cell E 0 cell (RT / )l K (ii) Whe the cocetratio decreases the umber of ios preset i uit volume of solutio decreases, as a result electrical coductivity decreases. (a) Galvaic cells, that are desiged to covert the eergy of combustio of fuels like H, CH 4, etc. directly ito electrical eergy are called fuel cells. They produce electricity with a efficiecy of about 70% ad are pollutio free. (b) Reactios takig place i Leclache cell Aode : Z(s) Z (aq) e Cathode : M (s) NH 4 (aq) e M() NH 3 (c) Z(s)Z (aq) Ag (s) Ag(s) (aq) 0 E E 0 (Ag cell /Ag) E 0 Z / Z E 0 (Ag /Ag) 0.344V ( 0.76 V) V Z(s) Ag (s) H (l) Z (aq)ag(s) (aq).303rt E 0 cell at 5 C log k c k c ati log (37.4) Sol. 0 (a) Lyophillic colloids-(i) They have strog forces of attractio betwee the dispersed phase ad dispersio medium. (ii) They are reversible i ature Lyobolic colloids (i) They have work force of attractio betwee the dispersed phase ad dispersio medium (ii) They are irreversible i ature. (Ay oe differece) CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # 3

4 (b) (i) Due to the scatterig of light by colloidal particles, the path of light becomes visible. The effect is called Tydall effect. The illumiated path of the beam of light is called Tydall coe. (ii) The colloidal particles get precipitated at oe of the electrodes, havig charge opposite to the charge they have. (iv) CH CH CHCH CH CH Butadiee C 6 H 5 Styree CH CHCH CH CH CH C 6 H 5 Bua-S Sol. 1 (A) Normal Pr otei Deatured Pr otei (B) (, 3 or 4 ) actors (always1 ) Nucleotide Nit.Base Petose H3P4 sugar (C) ph at which amio Acids do ot Migrate towards ay electrode. Sol. (A) Thermoset polymer : Due to extesive cross bods shape caot be chaged by heatig & coolig eg. Bakelite Thermoplastic polymer : Ubrached or less brached polymers Shape may be chaged by heatig & coolig (B) (i) CH CH (ii) CH CH CN (iii) HC CH CH PVC CH CH CN PAN C CH CH Sol. 3 (A)(i) Aspiri (ii) Paracetamol (iii) Bithiool C C (iv) Chloroxyleol NHC S H (B) Atacids Chemicals which reduces acidity i stomach e.g. (1) meprazole () Laso prazole Terphatlic Acid Ethylee Glycol (3) Al() 3 (4) Mg() etc CH C CH CH Terylee Sol. 4 (a) Ce 4 (b) (i)cr 7 3S 14 H Cr 3 3S 4 7H (ii)m 5e 8H 4 M 5e 3 4H CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # 4

5 Sol. 5 (a) Tras (b) [Ni 4 ] [Ni(C) 4 ] Ni [Ar] 4S 0 3d 8 Ni [Ar] 4s 3d 8 CH e 3 No violet colouratio 3d 4s 4p 3d 4s 4p C is strog field ligad sp 3 is weak field ligad sp 3 Sol. 6 I haloarees C X bod acquires a partial double bod character due to resoace. As a result the bod cleavage i haloarees is difficult tha haloalkaes ad therefore, they are less reactive towards ucleophilic substitutio reactio. X X X Θ Θ X X Θ (i) I reacts faster tha Br as iodie is a better leavig group because of its larger size. (ii) (1 halide) reacts faster tha ( ) 3 C (3 halide) sice i case tertiary butyl chloride three bulky methyl group hider the approachig ucleophile. Sol. 7 (i) Pheol gives a violet colouratio with e 3 solutio while bezyl alcohol does ot. 6C 6 H 5 e (Violetcolouratio) [(C H )6e] 3H 3H Bezyl alcohol (ii) Buta--ol whe warmed with NaI (I /Na) gives yellow precipitate iodoform while -Methylpropa--ol does ot give this test CH CH Buta--ol NaI Na H CH C 3NaI 3Na CHI 3 Na CH C CI 3 Iodoform (Yellow ppt.) C NaI No yellow ppt. -methyl propa--ol Sol. 8 (a) (i) Rate equatio d[c1 H 11] d[h ] Rate dt dt d[c H ] 1 6 dt (ii) Rate law equatio Rate K[C 1 H 11 ] (iii) Molecularity (iv) rder first order 6 d[c H (b) As the reactio is of first order therefore.303 P0 k log t P0 Pt whe t 100s (.303) (0.5) k log k (.303) / 100 log 1.5 (.303) / 100 (.0969) sec 1 dt ] CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # 5

6 Whe (a) Eergy P atm i.e. P 0 P 0.65 atm P 0.65 P atm Therefore the pressure of S at time t (P ) S P 0 P ( ) atm 0.35 atm Rate at that time K (P ) S atm sec 1 I the absece of catalyst I the presece of catalyst Sol. 9 (a) (i) due to icremet i bod legth Sol. 30 (ii) I its structure oly oe H is attached with H P H H (b) (i) Pb(N 3 ) Δ Pb 4N (ii) Xe H Δ Xe 4H (iii) Ca 3 P 6H 3Ca() PH 3 (a) (i) CH PCC CH aldol dil.na Path of reactio Effect of catalyst o activatio eergy (b) Because catalyst catalyses the forwards as well as backward reactio to the same extet. (c) Give K s 1 ; T 1 83 K K s 1 ; T?, Ea 60 KJ mol 1 K Ea T T1 log K1.303R T1 T log ( ) / ( ) T / ( ) T1 T1T log [(T 83) / 83T ] T 83 / K (97 73) C 4 C CH CH CH (ii) CH CH Mg Br H/H [] C (b) (A) Butyl butaoate (B) Butaoic acid (C) Butaol (D) But-1-ee CP Tower, Road No.1, IPIA, Kota (Raj.), Ph: Page # 6

Material Balances on Reactive Processes F&R

Material Balances on Reactive Processes F&R Material Balaces o Reactive Processes F&R 4.6-4.8 What does a reactio do to the geeral balace equatio? Accumulatio = I Out + Geeratio Cosumptio For a reactive process at steady-state, the geeral balace