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Sample Paper 2012

Class XIISubject Chemistry

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SELECTED QUESTIONS OF CHATE! :ALDEH"DE# $ETONE# CA!%O&"LIC

ACID AND O!'ANIC CO(OUND CONTAININ' NIT!O'EN

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Q. ). Suggest * +e*so, -o+ the *+ge 0--e+e,ce 0, the bo00,g po0,ts o- but*,o *,but*,*# *though the1 h*2e s*me soub00t1 0, w*te+.

A,s. The b. pt. of butanol is higher than that of butanal because butanol has strong

intermolecular H-bonding while butanal has weak dipole-dipole interaction. However

both of them form H-bonds with water and hence are soluble.

Q. 3. 4h1 HCOOH oes ,ot g02e H56 7He 5oh*, 6e0,s819 +e*ct0o, but

CHCOOH oes ;

A,s. CH3COOH contains hydrogens and hence give HV reaction but HCOOH does

not contain -hydrogen and hence does not give HV reaction.

Q. . 4h*t m*8es *cet0c *c0 * st+o,ge+ *c0 th*, phe,o ;

A,s. !reater resonance stabili"ation of acetate ion over pheno#ide ion.

Q.


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(ii) ethanoic acid gives Tollen+s reagent test whereas ethanoic acid does not due

to difference in their boiling points.Q. >. A++*,ge the -oow0,g 0, o+e+ o- 0,c+e*s0,g bo00,g po0,ts :

CHCH

3CH

3OH# CH

CH

3CH

3CH

# CH

CH

3? OCH

3CH

# CH

CH

3CH

3CHO

A,s. CH3CH

/CH

/CH

30 C

/H

1OC

/H

10 CH

3CH

/CH

/CHO 0 CH

3(CH

/)

/OH

(hydrogen) (ether) (aldehyde) (alcohol)

222222222222222222

increase in bond polarity.

Q. @. Athough phe,o0e 0o, h*s mo+e ,o. o- +eso,*t0,g st+uctu+es th*, c*+bo1*te

0o,# c*+bo10c *c0 0s * st+o,ge+ *c0. 4h1 ;

A,s. Conugate base of phenol 2 pheno#ide ion has non e4uivalent resonance structures

in which 5ve charge is at less electronegative C-atom and 6ve charge is at more

electronegative O-atom.

7esonance is not so effective.

OO

+

O

+

O

+

O

%n carbo#ylate ion8 5 ve charge is delocalised on two electronegative O-atoms hence

resonance is more effective

.

R C R C R C

O

O O

O O

O]

Q. B. A, o+g*,0c compou, w0th the moecu*+ -o+mu* CH

)O -o+ms 3#


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20go+ous o0*t0o,# 0t g02es )# 3be,Ge,e0c*+bo10c *c0. Ie,t0-1 the

compou,.A,s. (i) ince the given compound with . ,. C

9H

:;O forms a /8 ? derivative and

reduces Tollen+s reagent8 it must be an aldehyde.

(ii) ince it undergoes Canni"aro reaction8 therefore CHO gp. is directly attached

to the ben"ene ring.

(iii) ince on vigorous o#idation8 it gives :8 /-ben"ene dicarbo#ylic acid8 therefore

it must be an ortho substituted ben"aldehyde. The only o-substituted aromatic aldehyde

having . ,. C9H

:;O is /-ethyl ben"aldehyde. *ll the reactions can now be e#plained on the

basis of this structure

@*g (>H3)

/A6OH5 @OA

*g 6 2222222 2222

Tollen+s reagent

ilver

mirror /-ethyl ben"oate /-ethyl ben"aldehyde :8 /-ben"ene dicarbo#ylic acid

(. ,. C9H

:;O)

/8


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B:;. How will you distinguishD

(i) ?henol $en"oic *cid

(ii) $en"oic *cid 'thyl ben"oate.

*ns&- $y odiumbicarbonate test8 $en"oic acid gives effervescence.

COOH COO>a

E

6 >aHCO3 6 CO/ 6 H/O

?henol and ethyl ben"oate do not give this Test.

B:: How will you distinguish the following pairs&-

(i) ?entan- /-one and ?entan- 3-one

(ii) ?ropanol ?ropanal

(iii) ethanal 'thanal

O O

EE EE

*ns&- CH3-CH/-CH/-C-CH38 CH3-CH/- C-CH/-CH/

Fill !ive 6ve %odoform test =o not give 6ve %odoform test

(iii) ?ropanol will give sodium metal test.

?ropanol will give 6ve ,ehling+s olution Test

Question 12

An organic compound contains 69.77% carbon, 11.63% hydrogen

and rest oxygen. The moecuar mass o! the compound is "6. #t

does not reduce Toens$ reagent but !orms an addition compoundith sodium hydrogensuphite and gi&e positi&e iodo!orm test. 'n

&igorous oxidation it gi&es ethanoic and propanoic acid. (rite the

possibe structure o! the compound. )imp*

A+- % o! carbon 69.77 %

% o! hydrogen 11.63 %

% o! oxygen /100 )69.77 11.63*%

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Q.13

o i you prepare the !ooing compounds !rom ben;ene+itroben;oic acid

)iii* p>+itroben;oic acid )i&* ?henyacetic acid

)&* p>+itroben;adehyde.

A+-)i*




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)ii*

)iii*




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)i&*

)&*




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Q1@ *n organic compound G*+ with molecular formula CHO forms an orang e redprecipitate with /-< =>? reagent with yellow precipitate with on heating with iodine in

the presence of sodium hydro#ide. %t neither reduce Tollens or fehling reagent nor does it

decolori"e bromine water. On drastic o#idation with chromic acid8 it gives a carbo#ylic acid

($) having molecular formula n CIHJO/. %dentify the compound K*L and K$L and e#plain th e

reaction involved.

Q. ) Athough ? NH3gp 0s *, o+tho *, p*+* 0+ect0,g gp# ,0t+*t0o, o- *,00,e g02es

*o,g w0th o+tho *, p*+*# met* e+02*t02es *so.

A,s. >itration is carried out with a mi#ture of Conc. >O36 Conc. H

/O

ow 5 >H/gp in aniline is O8 p-directing and activating while 5> 6H

3

gp in anilinium ion is m-directing and deactivating hence a mi#ture of all three5ortho8

para and meta derivatives is formed.

Q. )>. 8bo- *,00,e 0s mo+e th*, th*t o- meth1 *m0,e.




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A,s. %n aniline8 the lone pair of electrons on the >-atom are delocali"ed over the ben"ene

ring. *s a result electron density on the nitrogen decreases. %n contrast in CH/

>H/

8 6 %

effect of CH3increase the electron density on the >-atom. Therefore8 aniline is a

weaker base than methylamine and hence its ?kb value is higher than that of

methylamine.

Q. )@ Accomp0sh the -oow0,g co,2e+s0o,s :

709 N0t+obe,Ge,e to be,Go0c *c0

7009 %e,G1 Cho+0e to 3phe,1eth*,*m0,e

A,s. (i) >a>O/

6 HCl

(i) ,eMHCl /I3 5 /I N CuC>MHC>

22222 22222 22222

(ii) >aOH =ia"oti"ation $en"ene

=ia"anium

*niline Chloride

$en"onitrile

H3

6O

22222

Hydrolysis

$en"oic acid

(ii)

NC> (a4) a*lH -hy is use of aspartame limited to cold food and drin!s?ol. 7spartame is unstable to heat and therefore it can be used as sugar substitutein cold drin!s and cold food only.

Q.11 what are artificial sweetening agents? Ii"e two e6amples?ol. ubstance which are used as sweetening agents in place of sugar but ha"e nonutriti"e "alue are called artificial sweetening agent. accharine and aspartame aree6ample of artificial sweetening agent.

Q.1# E6plain the following term with suitable e6ample?&7' ,ationic detergents&9' 7nionic detergent&,' Aeutral detergentol. ee the A,EB* te6t boo!.

Q.1# -hat are biodegradable and non2 biodegradable detergents? Ii"e onee6ample of each?ol. *he detergents which are decomposed by microorganisms li!e bacteria arecalled biodegradable and detergents are not decomposed by microorganism arecalled non2biodegradable detergents containing unbranched hydrocarbon chain arebiodegradable while the deterents containing branched hydrocarbon chain are non2biodegradable. (or e6ample n2lauryl sulphonate is biodegradable. On the other hand% adetergent such as shown below is non2biodegradable.

Q.1# Ii"e structural formula of aspirin% what is its chemical name?

Q.1) Ii"e the name one broad spectrum antibiotic?

Q.1+ -hat type of drug is chloramphenicol?

Q.10 Define the following and gi"e one e6ample of each &i' 7ntipyretics&ii' 7ntibiotics

Q.1/ 7ccount of the following

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&9' Diabetic patients are ad"ise to ta!e artificial sweeteners instead of naturalsweeteners.

CH'%C* N%>'T%C

Q. ). Out o- OaCl in water behaves like crystalloid while in

ben"ene behaves like colloid. imilarly dilute soap solution behaves like crystalloid whereas

concentrated soap solution like colloids. %t is the si"e of particles which matters i.e. the state

in which the substances e#ists. %f the si"e of the particles lies in the range : to :;;; no.8 it is

in colloidal state.

Q. Fhy it is necessary to remove CO when ammonia is obtained by Haber+s processD

A,s.& $ecause CO acts as poison for the catalyst in the manufacture of >H3by Haber+s process.

). Fhat is observed

(i) Fhen a beam of light is pressed through a colloidal sol

(ii) *n electrolyte8 >aCl is added to hydrated ferric o#ide sol.

(iii) 'lectric current is passed through colloidal sol.

A,s.& (i) Tyndal 'ffect

(ii) Coagulation

(iii) 'lectrophoresis

Q)). Fhat do you mean by activity and selectivity of catalysisD

A,s. *ctivity of catalyst means to increase the e#tent of chemisorption.

electivity of Catalyst means to direct a reaction to form selective product.




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Q)3 Fhat is -1D Fhat is its formulaD

A,s.& -1 is a "eolite seine of molecular porosity1. %ts formula is

H#@(*lO/)#(iO/)9J-#A . :JH/O

Q) Fhy adsorption is always e#othermicD

A,s.& %n *dsorption8 change of entropy Z is 5ve i.e. non favourable condition for e#othermic

change where as change of enthalpy ZH is 5ve i.e. favourable condition for e#othermic

change. Overall Z! becomes 5ve in adsorptionY therefore adsorption is always e#othermic.

:


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Q-11.()" s os&ot# 'ressure of 1 ,Cl s )$)er t)a! t)at of 1 urea soluto!s

Q-12.()at s re%erse os&oss :%e ts use.Q-13.6ef!e #oll$at%e 'ro'ert".Q-1.6raw a sutable a$ra& to e*'ress t)e relato!s)' for eal

soluto!s of > a! ? betwee! %a'our 'ressures a! &olefra#to!s of #o&'o!e!ts at #o!sta!t te&'erature.

Q-15.@)e %a'our 'ressure of 'ure A7us > a! ? are 8&& H$a!


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luto!.Q-2. How &a!" faraa"s of ele#tr#t" are re7ure to lberate

2 &oles of )"ro$e! $as ! ele#trol"ss of a soluto!Q-. ()at s t)e effe#t of a! !#rease ! #o!#e!trato! of 9!#

o!s o! t)e ele#troe 'ote!tal of 9!# ele#troe forw)#) E9!2+FG!e7uals .8

Q-. (rte a! e*'resso! to relate t)e &olar #o!u#t%t" ofele#trol"te ! ter&s of e$ree of sso#ato!.

Q-. Rust!$ of ro! s 7u#er ! sal!e water t)a! ! or!ar"water. ()" s t soQ-. ()at are se#o!ar" #ells

Q. How &a!" araa"s of #)ar$e are re7ure to #o!%ertID &ole of !O-to !2+o!4D &ole of Cr2O82-to Cr3+

Q-. (rte t)e #ell rea#to!s w)#) o##ur ! lea stora$ebatter" /0J w)e! t)e batter" s ! use a! /0 w)e! t)ebatter" s o! #)ar$!$.

Q-. How oes &olar #o!u#t%t" %ar" wt) #o!#e!trato! for/0 wea ele#trol"te a! for /0 Stro!$ ele#trol"te :%ereaso!s for t)ese %arato!s.

Q-. ()at s fuel #ell (rte #at)o# K a!o# rea#to!s ofH2-O2fuel #ell.Q-. Cal#ulate t)e E... of follow!$ #ell at 2$+/.10 D >$/s0:%e! I Eoe 2+ Fe =- . 4 Eo>$ + F>$ =- .; 4R = ;.31 L,-1&ol-14 1 = soluto! of N /NO302 s ele#trol"se betwee! 'lat!u&ele#troes us!$ a

#urre!t of 5. a&'eres for 2 &!utes4 ()at &ass of

N s e'oste at t)e#at)oe >t. (t of N = 5;.< u]Q-. ()e! a #erta! #o!u#t%t" #ell was flle wt) .1 ,CD4 t )as a

ressta!#e of ;5 o)& at 25 C. ()e! t)e sa&e #ell was flle wt)a! a7ueous soluto! of .52 u!!ow! ele#trol"te t)eressta!#e was


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#o!sta!t f #o!u#t%t" of .1 ,Cl soluto! at 2t 35 ,4 t)e sa&e rea#to! s 5P #o&'lete! 5 &!utes. Cal#ulate t)e a#t%ato! e!er$" for t)erea#to!.

Q-12. @)e follow!$ rate ata were obta!e at 3 , fort)e rea#to! I 2> + ? C + 6




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E*'t.

No.

>] &ol

A-1?] &ol A-

1

Rate of for&ato! of 6 / &ol

A-1 &!-10

1- .1 .1 . M 1-3

2- .3 .2 8.2 M 1-2

3- .3 . 2.;; M 1-1

- . .1 2. M 1-2

Cal#ulate t)e rate of for&ato! of 64 w)e! >] = .5 &olA-1a! ?] = .2 &ol A-1

Q-13. or a frst orer rea#to!4 t taes 5 &!utes for t)e!tal #o!#e!trato! of . &ol A-1to be#o&e . &ol A-1. How lo!$ wll t tae for t)e !tal #o!#e!trato! tobe#o&e .3 &ol A-1

Q-18. S)ow t)at ! a frst orer rea#to!4 t&e re7urefor #o&'leto! of


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'ENE!AL !INCILES AND

!OCESSES OF ISOLATION OFELE(ENTS

B-:. >ame the process in which a particular mineral is dissolved selectively

by using acids8 bases or other regents.

B-/. Fhat is the role of depressant in froth floatation processD

B-3. Out of C and CO8 which is a better reducing agent at JI3 ND

B-ame the processes by which chlorine is obtained as a by-product.

Fhat will happen if an a4ueous solution of >aC% is subected to

electrolysisD

B-::. !ive an account of the e#traction of silver by the cyanide process.

=escribe briefly how a pure sample of silver obtained by electro

refining.

B-:/. !iving e#amples8 differentiate between Groasting+ and Gcalcinations+.

B-:3. Fhy is the e#traction of copper from pyrite difficult than that from its

o#ide ore through reductionD

B-:


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*pe+ Subm0tte %1:

N*me A,0 sh*+m*

Em*0 *,0,sh*+m*

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