Uttarakhand Board Class 12 Question Paper 2023 for Chemistry

Uttarakhand Board
Question Paper
CLASS 12

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Roll No.
No. of printed pages : 8

130 43O (IGv!
2023
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CHEMISTRY (Theoryl
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Time:3Hoursl [Max.Ntrarks:70
ffitsr ' ( i) $H yqq qr ii StT 28 IIgq fl t sqft qqq srFrdrd d t

Directions:There are in all 28 questions in this question paper. AII questions are
compulsory.
(it) s'Fii tg ft€fRfr 3io r{b nqu oifua fl t

Marks alloted to the questions are mentioned against thern"
(iii) q-&6 qr{ 61 talqgd-o. qkd eren sgfu:tx'ftfre1
Read each question carefully and answer to the point"
( iv) ss{ riwr r a6frm#a qr{ tt {ff HFr b r#6 sT s at rtr{ fr ard futrro fr0 rre
f; r efr fr6g sTr+ ffi-<g@r C ftfuul gwT riwr z t z cffi Flk"rd rtftq q5
frt
Question No. 1 is multiple choice question. Four options are given in
answer of each part of this question. Write correct option in your answer
book. Question No. 2 to 7 are definite answer type questions.
(v) wq ssr 1 arr rd6 sus EF:im mr tt sqq \qwr z * z crF EEF 3i6 b Fq fll
ssT {sr s t r7 ffiF a+ 3iffi fu qs-{ €i wq rtwr 1B * 2s mffi #q sid & s$T
frt qr{'d@T 2G t 2s a# qrE dr# # wq frl
Each part of Question No. 1 carries one mark. Question No" 2 to 7 are of
one mark each. Question No. 8 to 17 are of two marks each. Question
No. 18 to 25 are of three marks each. Question No. 26 to 28 are of foua'
marks each.
(vi) Sfl qsr-qrT tt sqq w o'I$ ft6rq r& t nerfr 6fr,rq qFitfi ffi6
fr'om saq
fuqr rrqi tt t-S qst'i tt bam m fu6ru dtr fr rr< frfrst
There is no overall choice in this question paper, however, an internal
choice has been provided in few questions. Attempt only one of the given
choices in such questions.
ll l

[P.r.o.

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1 (6) FrgT fr $ rq tfe 6tmEs t" 1

(i) (tr (ii) ritd
(,ii) Ttr (iv) gq$ t oH cfi
In the foilowing the Lyophilic colloid is-
(i) Milk (ii) Gum
(iii) Blood (iv) None of these
(s) &H.ffiq*m-
(i) qftrdfr-o
1

(ii) ffirircft
(iii) ffi*ft (iv) frsffi
Penicillin is an-
(i) Antibiotic (ii) Antipyretic
(iii) Antiseptic (iv) Analgesic
(rT) fu$ mcrmq d m,fr * rdttft tr{ 6tdT tl 1

(i) ffiqn (ii) ffir;ra
(iii) ffiqc (iv) ffirqo
Deficiency of which vitamin causes nightblindness disease?
(i) Vitamin A (ii) Vitamin B
(iii) Vitamin C (iv) Vitamin D
(rT) rE6hT 61tflmffifr qffil'fr Bq-r HrdT d- 1

(i) $-{fot (ii) drsts+
(iii) qTds* (iv) UnFen+
Glucose is converted into Ethyl Alcohol by-
(i) trnveftase (ii) Zymase
(iii) Maltase (iv) Amylase
(s) FFq d t d*-{ ffirT f{ffiffi 6} sqqftrd o-sar *l 1

(i) tfuftm srqm (ii) *EtSm, 3rffi
(iii) ffi$ft6s6 iiv) wffi*srm
Which of the following reduces Fehling solution?
(i) Acetic Acid {ii) Benzoic Acid
(iii) Oxalic Acid (iv) Forr-nie Acid
(a) sf,{ffiffi d wP* ryffi ffi-ffikfr d - 1

(i) ffg{m (ii) lTt?r6
(iii) 3Tffir{rftF (iv) g+i + oH aA
The impurities present in the ore is called-
(i) Slag (ii) Ftux
(iii) Gangue (iv) None of these

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d

(E) ils#'{-6 6t'u6ms.d-
(i) UFffi{ (ii) s}fiq
1

(iii) EEfu (iv) ffid.m
The monomer of Nylon_6 is_
(i) Ethytene (ii) propene
(iii) Styrene
(H) *h* k** E6 * fr!-s-$ keq & rm #'ns?#racturn
(i) Bdfl?ro b rooo qrq tt -um,
(ii) ffir* furqa q
1

(iii) rry frex ft-drq* fr (iv) ftmc6 * zz.qmt* fr
A Molal solution is one that contains one Mole of
a solute in_
(i) 1000 gram of the sorvent (ii) one ritre of the sorution
(iii) one litre of the solvent (iv) 22.4 lrtres of the solution
2 Rm enq qRs,
ffi+HotaEdfr-fuaTtHb b vvryur#Sfiflr
1

Fill in the blank:
The soiubirity of a gas in a iiquid is direcry proportionar
3. 3TFrBur 2Hr -+ H, + r, o1gilEf,drdr q-dTsgl to the , ". of the gas.
1
Write the molecularity of reaction ZHI _+ H, + I,
4. 03, EcD erqffi sfr6#dtq6 of ora frqr dim-dr tl l
Why does O, act as a powerful oxidising agent?
s. Ko[Fe(cN)u] tt re fi
sffio{uT Tiwr aqi di 1
what is the oxidation number of Fe in Ko[Fe(cN)u]?
6. hddsur{arqnrqFro ftfuer ,bJ 1
Write chemical reaction of Aldol Condensation.
7. d*{ eisEdfrw ffiil<Tns fr adtrtsq H qqr$- ffi *l' fu \r\ 3rnThqT
-'-\r rrwr{6
frfuEl 1
How chiorobenzene is prepared from Benzene
Diazonium chioride? write
chemical reaction only.
8. Pfrqo} dq 3flr fibcT dq tf H-rr wv mtfre
t Z
Differentiate between schottky defect and Frenker
defect.
e. HItlI{ui E-Sq, 3ia'ffi6 q-fu sflx mmm-b6-d q,+q
u-om d6fmt qrrem miffis
aw qd.6 st qfr ro-or olko.r fr q-{qln$fi of ger dqflT vmgdr Z
Explain simple cubic, body centred cubic
and face centred cubic unit cells and find
the total number of atorns per unit cell of each.
3IEEil/OR

430 (rcv)
t31 I P.T.O.

trdn aEI et 61fudTfi rircrqT srd' bfu q+q (bcc) tr mtRroi d 6t of mgqr$ zea
p, t dstT ffiI6T tFtci 7.2 s/cm3 tl W ae b 208 qrq C ffi q{qlg sqRra dl
An element has a body-centred cubic (bcc) structure with a cell edge of
288 prn. The density of the element is 7.2 g/cms. How many atoms are present
in 20E g of this elernent?
10. trqftRroq(€fleiqft;quftft{fus- !x2=2
Write shont notes on the following-
(6) *q krffi BB (s) rnEto
Froth floatation Method Flux
11. dxT* b frqd 3ilffirr{ b froe ftRssr 2

State the Faraday's Laws of electrolysis.
12. HrrsgcrdE s*-< vee-gm-s dr uo-s-6 5dr6{ur HRd vsflrsut 2
Explain homopolymer and copolymer each with an example"
13" [Nict4]-,3rgffifr1rrt, ildfu [Ni(co)"] qfrgry#q*, ?rtr&daf apm-*ludl oqil
2

IP.i!Ctr4]-'Z is pararnagnetic, while INi(CO)4] is diamagnetic, thor"lgh both are
tetnahedrai. Why?
STerdIT/OR

ftqfrfum ml rm-um rtrf,{q rift-f, sq-flr$?- Lx2=2
Explain the foilowing each with an exarnple-
tffi) ffifr-frqqqrrffrf,T (s) qffiTRffisrilcrqqfrT
Geornetrical Isomenism Optica! Isornerlsn'l
i.4. 1foqfri.kae{WFr6f{qTETfrfus- Lx2=Z
Wnite down the electronic configuration of the following-
(6) Cr*3 (g.) cu*
1s. m*hSffiq fr BqfuTa dft-q qslqI, UFrd ddr<lns fr wfurd ffifr-q q{qTql at erteli oq'
&?Tr#c{ r}m *, adii Z

Why Chlorine atom present in Chlorobenzene is less reactive than ehlorine atom
pnesent in Ethyl Chloride?
16. ffirgq ffiJr rffrmry 3flqTfo d :r*.r< EE ditfus I z
Dlfferentiate between Soap and Synthetic Detergents.

430(rcv) I1l

a

t7 , frH Trilqf{s srftTBqr bt BqTEftT frfuu - 2
write down the mechanism of the foilouring chemical reaction-

H
-l R-C-X-@ +Xl
Nu:+
H
l= -d[l-d (Pr oduct)

18. ffirRna qii 61 qfufiFd 6tBu- 1x3=3
Define the following terms-
(6) Tlff,dr (s) fim-{f,r (rT) q15 qt].r,
Normality Molarity Molar fraction
sstrIr/oR
4 qE brkd etsl 13i[t1r< 40) fr\ flfr tt u}f,6q 200 qr+ EiltrT d;TrqT rrqrr
fr'mqq afi'
ddo,dT 3lr< fr-dq 6-r d'm'qr+rfr sro m*t g
4 gm of caustic soda (molar rnass 40) is dissolved in water to prepare 200 grn
of solution' Calculate the molality of the solution and molar fraction of the
solute.
1e. fuqfrfud a1 m'nur qtrd sq-flrEu-
Explain the following with reason-
(6) fu)-{r5su-S-d{ Z
Lanthanoid Contnaction
(tr) d-ffi b am v?fq 3ilzn eqrfr dr 1

d-block elements forrn coloured ions.
za, fuqftfuc mt mr<or HRd qrsrr otffis- 1x3=3
Explaln the following with reason*
(6) $6-GI (u) Enrm st1rq (rr) 3Tfi6-{
eoagulation Tyndal Effect Dialysis
2t , @r fur d aq (&Tm <rfltqfrdr Hqtopr ftfout - 1 x 3= 3
What happens when {Write chemical equation only) _
(6) tfirn fufttdrd d frqr q{R frt sqfuifr fr 3rrzr&q t orfr dr
Ethyl Alcohol is treated with Iodine in presence of Alkali.
1q'1 ffiffii mi blt'Im der rfrfrrrq riBTrffii$s il frmq{ b nrer rr$ mr& dr
Chloroforrn is heated with ttre solution of Phenol and Sodiurn Hydroxide.

430(IGV)

Isl [P.r.o.

.,

(TT)tf}Idt.dr6d6.rtfrtrdffiffi&qrqwiaxtdi
Ethyl Alcohol is heated with Acetic Acid'
22. qrerfrr*, frfi*" ud E€Fr6 tftit fi
qran # ffi E6 frRr 6r dutE mtfrE r HdfEIn
srF{bqrciie'ffiHfiowTfifrftsEl
of primary, secondary and tertiary
3

Describe any one method for the identification
for the reactions involved'
amines. write the chemical equations also
23.6KqHtrni$rffiissfup-ffioildrbF"PFfisaW'"i863{HdttdFi*atierlq-{
1x3=3
d*qfuffindltd- trend
properties of p-block elements
Explain with reason how the following
while moving from left to right in a penod-
(6) qGlo]kflr (s) $r{qqs-di (n) frgdftqrfroa
ElectronegativitY
Atomic radius lonisation energy
S[elEII/oR
1x3=3
Fr+qft{Rrd b or<ur Ahu-
Give reasons of the following-
(6) H2o Eo ffifu H,s +s
t tl
HrO is liquid while HrS is gas'
tsl otg)trs pcts d;ridr t ffifu qTnfrG_{ NCi. T€ieqrdT d't
PhosphorusformsPCl,whileNitrogendoesnotformsNCl,.
(rr) .,- ,rr* 6.r liltsT{ Cl q{qTql t wi dmr t t

ThesizeofCl_ionisgreaterthanthesizeofClatom'
6en qMdr$s d g<< ss frBul
2
24. (6) qffiq6
Differentiatebetweennucleosidesandnucleotides.
(s) Dt\A 3ik RNA it w 3{<R d-drsEl
1

Give one difference between DNA and RNA'
t
25. (6) mYf,{ripT b Frq-q ol ftRsut
State Kohlraush's l-aw'
qlE?F sfr (e,m,f,) # wrfl #tss- 2
1q1 frq +fl b fte zsoc u< frgo
Calcr.rlate the electromotive force (e.m,f.)
of the following cell at 250C-

ZnlZn*? (0.01M) I lAg.(1'0M) | Ag
tro =1.56V (at 25oC)
L cell-lrJvY

3[srfl/oR

430 (rGV) t6l

I

(6) iiEurflffi<urffigsr 1

Write the Nernst Equation.
tqqt frq ffii& frs, +n sTFiM ftTfuu- Z

Write cell reactions for the following cells-
(i) FelFs+zl lHrS04lHr(pt)
(ii) (Pt)H,lHCt ll ctr(Pt)
26. (6) qefislE#3{nrBqTbftrs t{rrrfrowTd%iqfrdful 3
Derive the integrated rate equation for the first order reaction.
(s) Em seiq o'lE d 3TRTh??T m.r trr Rr<i-6 2. 31 x 10-5 ilol * r w 3rFTB-qT m1 sr*JsTrg
sra frBst 1

A first order reaction has rate constant 2.31xtr0-s sec-1. Calculate the
half-life of the reaction.
3{erdr/oR
(6) RE fiBu fu qet'q s1fr ffit 3{ftTfur ti se*2" $frTBqT X$ *+ tf arr srrcr, eoCI/o
3Tnfu glf di d dt ssrq 6T grfdT 6rnT *t z
Prove that the time required for 99olo completion of a first order reactlon is
twice the time required for the completion of 90olo reaction.
(q) rrsffim3TFTfurToTvrgk-dffifrfu1 z
Write Collision Theory of Chemical Reactions.
27. HdqR6 sIffi b fufuT fr $nrqf frfh mr rrqifud fte HRa EUh dBs HqT $dRrd
vglqFffi 3TnTfrqrE frfur rrqfto 3rffi & d\ ffi{irr fr rcmger 4
Describe Contact method for the manufacture of Sulphuric acid with labelled
diagram and write the chemical reactions involved. Give two uses of Sulphuric
acid also,
$erqr/oR
(6) 3rqlFrqT a gilEilFro Frqfq h aE{ sfr-g 6i nftT auh fiEru dpn sfu?Tr * rrdErd
rrgrqfr-o s+fl+B-qnfib sfroqTr S ffisBr 3
Describe Haber's process for the manufacture of Amr:ronia with diagram
and write the chemical reactions involved during the process.
(s) drrT ddr t ilq d& of rrs HFfr qrqqRo 3Fm * frrn arqrd $p 1

What happens when copper is treated with hot concentrated sulphurlc acid.

430 (rGV) I7l IP.T.O.

28. (6) 116 6rdfr6 dFffi A (3rgqx c3H6o) dd-{ 3{Fr6tr6 b erq GEqr rfr $krr t, fuE
3,{rla-{Fr m<t r< dftr6 B (c,H8o) srrflT tl dfiro s # F{ar t
fr.qr ovi qt
dmrgs c v.rdT t, Eil ffi-rrftro ron *'frqr 6Tb ffiq D (c3H6) u{-ar tt
dFr6 A, B, c aw o # qtdH 3rrqwr?F <tsrqfrm srFfu3iisFo dfrut 3
An organic compound A (molecular formula C3H6O) does not react with
Tollen's reagent but on reduction gives compound B (C3l-{sO). Cornpound
B, on treatment with HB6 gives Bromide C, which on treatment with
alcoholic KOH gives Alkene D (C3H6). Identify compou.rnds A, B, C and D
with essential chemical reactions.
(Er) rrcrcrFt-otq STFTBqT o\ <rsrqFffi nft'o.-{ur Htrd ftfust 1

Write down the Gattermann-Koch reaction with chemical equation.
$srqT/oR.
frq rrsrqFro rffi fr fts efi=it C sna rn'rii 6\ r{b ildi Sk Tgrqktr q* Hkd
frR g- tx4=4
In following chemical equationsu write down the products obtained with thein
names and chemical formulae in the blank spaces -
o
(6) il Pd/Ba
Hsc - -cl
C s, Jd-f,ft
Boiling Xyiene

COOH
KOH,
(s) H:0n
COOH

o
(rT) * 50o/o NaOH
- U- H A
HCOONa +

(tJ) (CH3COO)2 Ca -------r CaCO, +

*****

430 (rGV) l8l

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