Rajasthan Board Class 12 Question Paper 2019 Chemistry

Zm_m§H$ Roll No.

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Sl.No. :

No. of Questions – 30 SS–41–Chem.
No. of Printed Pages – 11

Cƒ _mÜ`{_H$ narjm, 2019
SENIOR SECONDARY EXAMINATION, 2019
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TEAR HERE TO OPEN THE QUESTION PAPER
CHEMISTRY
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àíZ nÌ H$mo ImobZo Ho$ {bE `hm± \$m‹S>|
nyUmªH$ : 56

Zmo Q >: g‘rH$aUm| H$mo Amdí¶H$ eVm] g{hV g§ V w { bV ê$n ‘| {b{IE&

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GENERAL INSTRUCTIONS TO THE EXAMINEES :

1) narjmWu gd©àW_ AnZo àíZ nÌ na Zm_m§H$ A{Zdm`©V… {bI| &
Candidate must write first his / her Roll No. on the question paper
compulsorily.

2) g^r àíZ hb H$aZo A{Zdm`© h¢ &
All the questions are compulsory.

3) àË`oH$ àíZ H$m CÎma Xr JB© CÎma-nwpñVH$m _| hr {bI| &
Write the answer to each question in the given answer-book only.

4) {OZ àíZm| ‘| AmÝV[aH$ IÊS> h¢, CZ g^r Ho$ CÎma EH$ gmW hr {bI|&
`hm± go H$m{Q>E

For questions having more than one part the answers to those parts are to
be written together in continuity.

SS–41–Chem. 1333 [ Turn Over

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5) àíZ nÌ Ho$ {hÝXr d A§J«oOr ê$nmÝVa ‘| {H$gr àH$ma H$s Ìw{Q> / AÝVa / {damoYm^mg hmoZo na {hÝXr ^mfm Ho$
àíZ H$mo ghr ‘mZ|&
If there is any error / difference / contradiction in Hindi & English versions of
the question paper, the question of Hindi version should be treated valid.

6) àíZ g§ » ¶m A§ H $ à˶o H $ àíZ
1 - 13 1
14 - 24 2
25 - 27 3
28 - 30 4
Q.Nos. Marks per question
1 - 13 1
14 - 24 2
25 - 27 3
28 - 30 4

7) àíZ H«$‘m§H$ 21, 27, 28, 29 d 30 ‘| AmÝV[aH$ {dH$ën h¢&
Question Nos. 21, 27, 28, 29 and 30 have internal choices.

IÊS> - A
SECTION - A

1) ZoQ>dH©$ R>mog H$m H$moB© EH$ CXmhaU {b{IE & [1]
Write any one example of network solid.

2) pñWaŠdmWr {_lU H$s n[a^mfm {b{IE & [1]
Write definition of azeotropic mixture.

SS–41–Chem. 1333

3
3) EH$ amgm`{ZH$ A{^{H«$`m H$m doJ {Z`Vm§H$ 1.72 × 10–4 s–1 h¡& A{^{H«$`m H$s H$mo{Q> kmV H$s{OE & [1]
Rate constant of a chemical reaction is 1.72 × 10–4 s–1. Calculate the order of
reaction.

4) Xohbr D$Om© H$mo n[a^m{fV H$s{OE & [1]
Define threshold energy.

5) {ÛXÝVwH$ {bJÝS> H$m H$moB© EH$ CXmhaU Xr{OE & [1]
Give any one example of bidentate ligand.

6) S>mBE{Wb B©Wa H$m IUPAC Zm_ {b{IE & [1]
Write IUPAC name of Diethyl ether.

7) µ\$sZm°ŠgmBS> Am`Z H$s AZwZmXr g§aMZmE± ~ZmBE & [1]
Draw the resonating structures of phenoxide ion.

8) H$m{~©bEo_rZ A{^{H«$`m H$m amgm`{ZH$ g_rH$aU {b{IE & [1]
Write chemical equation of carbylamine reaction.

9) WmBamBS> J«§{W Ûmam óm{dV hm_m}Z H$m Zm_ {b{IE & [1]
Write name of the hormone secreted by thyroid gland.

10) O¡d{ZåZrH¥$V ~hþbH$ H$m H$moB© EH$ CXmhaU {b{IE & [1]
Write any one example of biodegradable polymer.

11) ã`yZm-N ~hþbH$ H$s EH$bH$ BH$mB`m± {b{IE & [1]
Write monomer units of polymer Buna-N.

12) ~hþbH$ Ho$ {bE ~hþn[ajonU KmVm§H$ Š`m h¡? [1]
What is polydispersity index for a polymer?

13) H2O AUw _| CnpñWV g_{_{V Aj H$m _mZ (Cn) {b{IE & [1]
Write the value of axis of symmetry (Cn) present in H2O molecule.

SS–41–Chem. 1333 [ Turn Over

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IÊS> - ~
SECTION - B
14) A) em°Q²>H$s Ed§ \«|$H$b Xmof _| H$moB© Xmo A§Va {b{IE &
~) gab KZr` OmbH$ _| g§Hw$bZ XjVm H$s JUZm H$s{OE &
[1 + 1 = 2]
A) Write any two differences between Schottky and Frenkel defects.
B) Calculate the packing efficiency in simple cubic lattice.

15) K4[Fe(CN)6] H$m 0.05M {db`Z 300K na 92% {d`mo{OV hmoVm h¡& {db`Z H$m namgaU Xm~ kmV
H$s{OE & (R = 0.0821 dm`w_§S>b brQ>a K–1 mol–1) [2]
0.05M solution of K4[Fe(CN)6] at 300K is 92% dissociated. Calculate the osmotic
pressure of the solution. (R = 0.0821 atm. LK–1 mol–1)

16) A) {dÚwV AnKQ>`m| Ho$ MmbH$Ëd H$mo à^m{dV H$aZo dmbo H$moB© Xmo H$maH$ {b{IE &
~) g§jmaU EH$ d¡ÚwV amgm`{ZH$ n[aKQ>Zm h¡ & g_PmBE &
[1 + 1 = 2]
A) Write any two factors which affects the conductance of electrolysis.
B) Corrosion is an electrochemical phenomenon. Explain.

17) 298K na 0.10M KCl {db`Z H$s MmbH$Vm 0.0129 s cm–1 h¡& BgH$s _moba MmbH$Vm H$m
n[aH$bZ H$s{OE & [2]
The conductivity of 0.10M solution of KCl at 298K is 0.0129 s cm–1. Calculate
its molar conductivity.

18) EH$ àW_ H$mo{Q> H$s A{^{H«$`m _| 20% {d`moOZ hmoZo _| 40 {_ZQ> bJVo h¢ & AYm©`w H$s JUZm H$s{OE &
(log1010 = 1, log102 = 0.3010) [2]
A first order reaction takes 40 minute for 20% decomposition. Calculate half
life. (log1010 = 1, log102 = 0.3010)

SS–41–Chem. 1333

5
19) A) Eobw{_{Z`_ Ho$ d¡ÚwV-YmVwH$_© _| J«¡\$mBQ> N>‹S> H$s Š`m ^y{_H$m h¡?
~) namdV©Zr ^Å>r H$m Zm_m§{H$V {MÌ ~ZmBE &
[1 + 1 = 2]
A) What is the role of graphite rod in the electrometallurgy of aluminium?
B) Draw a labelled diagram of reverberatory furnace.

20) {ZåZ{b{IV g§Hw$bm| _| Ho$ÝÐr` YmVw Am`Z H$s Am°ŠgrH$aU AdñWm Ed§ Cnghg§`moOZ g§»`m Xr{OE & [2]
A) [Co(en)3]3+ ~) K4[Fe(CN)6]
Give the oxidation state and coordination number of the central metal ion in the
following complexes.
A) [Co(en)3]3+ B) K4[Fe(CN)6]

21) A) EoëH$mohm°b H$s VwbZm _| µ\$sZm°b A{YH$ Aåbr` Š`m| hmoVr h¡? g_PmBE &
~) {ZåZ{b{IV EoëH$mohm°bm| H$mo EñQ>arH$aU A{^{H«$`m Ho$ à{V CZH$s ~‹T>Vr A{^{H«$`merbVm Ho$ H«$_ _|
ì`dpñWV H$s{OE &
CH3–CH2–OH, (CH3)2CH–OH, (CH3)3C–OH
[1 + 1= 2]
AWdm
A) EoëH$mohm°bm| H$m ŠdWZm§H$ g_Vwë` AmpÊdH$ ^ma dmbo hmBS´>moH$m~©Zm| Ed§ B©Wa go A{YH$ Š`m| hmoVo h¢?
g_PmBE &
~) {ZåZ{b{IV EoëH$mohm°bm| H$mo {ZO©brH$aU A{^{H«$`m Ho$ à{V CZH$s ~‹T>Vr A{^{H«$`merbVm Ho$ H«$_ _|
ì`dpñWV H$s{OE &
CH3–CH2–OH, (CH3)2CH–OH, (CH3)3C–OH
A) Why phenol are more acidic than alcohol? Explain.
B) Arrange the following alcohols in increasing order of their reactivity towards
esterification reaction.
CH3–CH2–OH, (CH3)2CH–OH, (CH3)3C–OH
OR
A) Why the boiling points of alcohols are higher than hydrocarbons and ethers
of comparable molecular mass? Explain.
B) Arrange the following alcohols in increasing order of their reactivity towards
dehydration reaction.
CH3–CH2–OH, (CH3)2CH–OH, (CH3)3C–OH

SS–41–Chem. 1333 [ Turn Over

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22) {ZåZ{b{IV amgm`{ZH$ A{^{H«$`mAm| _| [A] Ed§ [B] H$mo nhMm{ZE & [2]
C 6 H 5 N 2+ Cl     [A] 
Cu (MyU©)
NaNO 2 (Obr`)

Sn HCl
6[H]
 [B]
Identify [A] and [B] in the following chemical reactions.
C6 H 5 N 2+Cl 
Sn HCl
Cu(Powder)
NaNO 2 (Aqueous)
 [A] 
6[H]
 [B]

23) A) Š`m hmoVm h¡ O~ ½byH$mog gmÝÐ HNO3 go A{^{H«$`m H$aVm h¡? amgm`{ZH$ g_rH$aU Xr{OE &
~) -D-amB~mog eH©$am H$s g§aMZm ~ZmBE &
[1 + 1 = 2]
A) What happen's when glucose reacts with concentrated HNO3? Give chemical
equation.
B) Draw the structure of -D-ribose sugar.

24) A) {dÝ`mgr Ed§ g§ê$nr` g_md`{d`m| _| {d^oX H$s{OE &
~) gmBŠbmohoŠgoZ H$m Hw$gu g§ê$n, Zm¡H$m g§ê$n go A{YH$ ñWm`r hmoVm h¡& g_PmBE &
[1 + 1 = 2]
A) Differentiate between configurational and conformational isomers.
B) The chair conformer of cyclohexane is more stable than boat conformer.
Explain.

IÊS> - g
SECTION - C
25) {X`o J`o CÕaU H$mo n‹T>H$a AYmo{b{IV àíZm| Ho$ CÎma Xr{OE &
AmYww{ZH$ AmdV© gmaUr Ho$ Xþb©^ _¥Xm VËd b¡ÝWoZm°`‹S> H$hbmVo h¢& AmdV© gmaUr _| BZH$m n¥WH$ ãbm°H$
h¡& b¡ÝWoZm°`‹S> loUr _| gr[a`_ (na_mUw H«$_m§H$ - 58) go àma§^ hmoH$a ë`yQ>o{e`_ (na_mUw H«$_m§H$ - 71)
VH$ Ho$ 14 VËd hmoVo h¢ & g^r b¡ÝWoZm°`S> gm_mÝ`V`m +3 Am°ŠgrH$aU AdñWm Xem©Vo h¢& BgHo$ A{V[aº$ Hw$N>
b¡ÝWoZm°`S> +2 d +4 Am°ŠgrH$aU AdñWm ^r Xem©Vo h¢& b¡ÝWoZm°`S> loUr _| ~mBª go XmBª Amoa OmZo na na_mUw
Ho$ AmH$ma _| {Z`{_V ömg nm`m OmVm h¡ Bgo b¡ÝWoZm°`S> g§Hw$MZ H$hVo h¢ & b¡ÝWoZm°`S>m| Ho$ H$B© Am¡Úmo{JH$
Cn`moJ O¡go - {_eYmVw H$m {Z_m©U, OoQ> B§{OZ Ho$ H$b nwO} ~ZmZ| _| hmoVm h¡&
A) b¡ÝWoZm°`S> VËdm| Ho$ hmBS´>m°ŠgmBS>m| H$s jmar` àH¥${V ~mBª go XmBª Amoa OmZo na KQ>Vr h¡& g_PmBE &
~) {_eYmVw Ho$ {Z_m©U _o§ à`wº$ Xmo b¡ÝWoZm°`S> VËdm| Ho$ Zm_ {b{IE &
g) +4 Am°ŠgrH$aU AdñWm Xem©Zo dmbo {H$gr EH$ b¡ÝWoZm°`S> VËd H$m Zm_ {b{IE &
[1 + 1 + 1 = 3]
SS–41–Chem. 1333

7
Read the given paragraph and give answers of the following questions.

The rare earth elements of the modern periodic table are known as
lanthanoids. They have separate block in periodic table. The lanthanoid series
consist of fourteen elements starting from Cerium (atomic number - 58) to
Lutetium (atomic number - 71). All lanthanoids generally exhibit +3 oxidation
state. In addition some lanthanoids show +2 and +4 oxidation state also. As we
move from left to right in lanthanoid series there is regular decrease in the size of
an atom. This is known as lanthanoid contraction. There are many industrial
application as - formation of mischmetal, production of parts of Jet engine.

A) The basic nature of hydroxides of lanthanoid elements decreases moving
from left to right. Explain.

B) Write name of two lanthanoid elements used in the formation of mischmetal.

C) Write the name of any one lanthanoid element exhibiting +4 oxidation
state.

26) {X`o J`o CÕaU H$mo n‹T>H$a AYmo{b{IV àíZm| Ho$ CÎma {b{IE &

agm`Zm| H$m X¡{ZH$ OrdZ Ho$ {d{^Þ joÌm| _| {deof _hËd h¡ O¡go - ImÚ nXmWm] _|, gm~wZ Ed§
An_mO©H$m| _| ImÚ nXmWm] H$mo n[aa{jV H$aZo _|, AmH$f©U ~T>mZo Ed§ nm¡{ï>H$ JwUdÎmm ~‹T>mZo _| agm`Zm| H$m
Cn`moJ {H$`m OmVm h¡& do agm`Z Omo ImÚ nXmWm] H$mo bå~o g_` VH$ Iam~ hmoZo go ~MmZo Ed§ nm¡fUr` _mZ
~Zm`o aIZo Ho$ {bE {_bm`o OmVo h¢ ImÚ n[aajH$ H$hbmVo h¢& H¥${Ì_ _YwaH$ do amgm`{ZH$ `m¡{JH$ hmoVo h¢ Omo
ImÚ nXmWm] H$mo {_R>mg XoZo _§o à`wº$ hmoVo h¢ & _Yw_oh Ho$ amo{J`m| H$mo eH©$am Ho$ ñWmZ na g¡H$arZ H$m à`moJ H$aZo
H$s gbmh Xr OmVr h¡&

A) ImÚ nXmWm] _| agm`Z Š`m| {_bmVo h¡?

~) {H$Ýht Xmo ImÚ n[aajH$m| Ho$ Zm_ {b{IE &

g) _Yw_oh Ho$ amo{J`m| H$mo g¡H$arZ Ho$ à`moJ H$s gbmh Š`m| Xr OmVr h¡?

[1 + 1 + 1 = 3]

SS–41–Chem. 1333 [ Turn Over

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Read the given paragraph and write answers of the following questions.
Chemicals have special importance in various field of daily life as - in
foods, in soap and detergents. Chemicals are used in food materials for
preservation, to enhance appeal and to increase its nutritive quality in them.
Chemical substance which are added to the food materials to prevent their spoilage
and retain their nutritive value for long times are called food preservatives. Artificial
sweeteners are those chemical compounds which are used to give sweetening
effect to the food materials. Diabetic patients are advised to used saccharin in
place of sugar.
A) Why chemicals are added in food materials?
B) Write name of any two food preservatives.
C) Why diabetic patients are advised to used saccharin.

27) A) Am°Šgo{bH$ Aåb H$m g§aMZm gyÌ {b{IE &
~) EoëS>m°b g§KZZ H$s {H«$`m{d{Y g_PmBE &
[1 + 2 = 3]
AWdm
A) S>mBE{Wb H$sQ>moZ H$m g§aMZm gyÌ {b{IE &
~) H$moë~o d¡ÚwV AnKQ>Z H$s {H«$`m{d{Y g_PmBE &
A) Write structural formula of oxalic acid.
B) Explain mechanism of Aldol condensation.
OR
A) Write structural formula of Diethyl ketone.
B) Explain mechanism of Kolbe electrolysis.

IÊS> - X
SECTION - D
28) A) A{YemofU H$s n[a^mfm {b{IE &
~) Š`m hmoVm h¡ O~ H$mobm°BS>r {db`Z _| {dÚwV Ymam àdm{hV H$s OmVr h¡?
g) Ob Ho$ ew{ÕH$aU hoVw {\$Q>H$ar Š`m| {_bmVo h¢?
X) H$mobm°BS>r {db`Zm| Ho$ ew{ÕH$aU H$s d¡ÚwV AnmohZ {d{Y H$m Zm_m§{H$V {MÌ ~ZmBE &
[1 + 1 + 1 + 1 = 4]

SS–41–Chem. 1333

9
AWdm

A) amgm`{ZH$ A{YemofU H$s n[a^mfm {b{IE &

~) Š`m hmoVm h¡ O~ àH$me nw§O H$mobm°BS>r {db`Z _| go J_Z H$aVm h¡?

g) AmH$me H$m a§J Zrbm Š`m| {XImB© XoVm h¡?

X) H$m°Q´>ob Yy_« AdjonH$ H$m Zm_m§{H$V {MÌ ~ZmBE &

A) Write definition of adsorption.

B) What happen's when an electric current is passed through colloidal solution?

C) Why alum is added for purification of water?

D) Draw a labelled diagram of electro-dialysis method for purification of colloidal
solutions.

OR

A) Write definition of chemical adsorption.

B) What happen's when a beam of light is passed through the colloidal solution?

C) Why the colour of sky appears blue?

D) Draw a labelled diagram of cottrell smoke precipitator.

29) A) ZmB{Q´>H$ Aåb _| ZmBQ´>moOZ H$s Am°ŠgrH$aU AdñWm {b{IE &

~) Š`m hmoVm h¡ O~ gë\$a gmÝÐ H2SO4 go A{^{H«$`m H$aVm h¡? amgm`{ZH$ g_rH$aU Xr{OE &

g) AmYw{ZH$ JmoVmImoar CnH$aUm| _| hr{b`_ H$m Cn`moJ Am°ŠgrOZ Ho$ VZwH$mar Ho$ én _| Š`m| {H$`m OmVm
h¡? g_PmBE &

X) HClO3 H$s g§aMZm ~ZmBE &

[1 + 1 + 1 + 1 = 4]
SS–41–Chem. 1333 [ Turn Over

10
AWdm
A) A_mo{Z`m _| ZmBQ´>moOZ na_mUw H$s g§H$[aV AdñWm {b{IE &
~) Š`m hmoVm h¡ O~ H$m~©Z gmÝÐ H2SO4 go A{^{H«$`m H$aVm h¡? amgm`{ZH$ g_rH$aU Xr{OE &
g) h¡bmoOZ `m¡{JH$m| H$s VwbZm _| A§Vamh¡bmoOZ `m¡{JH$ A{YH$ {H«$`merb Š`m| hmoVo h¢? g_PmBE &
X) XeF6 H$s g§aMZm ~ZmBE &
A) Write oxidation state of nitrogen in nitric acid.
B) What happen's when sulphur reacts with concentrated H2SO4? Give chemical
equation.
C) Why helium is used as diluent for oxygen in modern diving apparatus?
Explain.
D) Draw the structure of HClO3.
OR
A) Write hybridised state of nitrogen atom in ammonia.
B) What happen's when carbon reacts with concentrated H2SO4? Give chemical
equation.
C) Why interhalogen compounds are more reactive than halogen compounds?
Explain.
D) Draw the structure of XeF6.

30) A) q\$Ho$ëñQ>mBZ A{^{H«$`m H$m amgm`{ZH$ g_rH$aU {b{IE &
~) Eo[ab h¡bmBS> Zm{^H$ñZohr à{VñWmnZ A{^{H«$`mAm| Ho$ à{V H$_ {H«$`merb Š`m| hmoVo h¡? g_PmBE &
g) {ZåZ{b{IV EopëH$b h¡bmBS>m| H$mo SN2 A{^{H«$`m Ho$ à{V CZH$s A{^{H«$`merbVm Ho$ ~‹T>Vo H«$_ _|
ì`dpñWV H$s{OE &
CH3–CH2–Cl, (CH3)2CH–Cl, (CH3)3C–Cl
X) CH3Cl H$m H$jH$ AmaoI ~ZmBE &
[1 + 1 + 1 + 1 = 4]

SS–41–Chem. 1333

11
AWdm
A) dwQ>©²O - {\${Q>J A{^{H«$`m H$m amgm`{ZH$ g_rH$aU {b{IE &
~) EopëH$b ŠbmoamBS> H$s Obr` KOH go A{^{H«$`m H$amZo na EoëH$mohm°b ~ZVm h¡ O~{H$ EoëH$mohm°{bH$
KOH H$s CnpñW{V _| EoëH$sZ _w»` CËnmX Ho$ ê$n _| àmá hmoVr h¡& g_PmBE &
g) {ZåZ{b{IV h¡bmoOZ ì`wËnÞm| H$mo Zm{^H$ ñZohr à{VñWmnZ A{^{H«$`mAm| Ho$ à{V ~‹T>Vr A{^{H«$`merbVm
Ho$ H«$_ ì`dpñWV H$s{OE &

R–Cl, –Cl, –CH2–Cl

X) Šbmoamo\$m_© Ho$ {daMZ H$s à`moJembm {d{Y H$m Zm_m§{H$V {MÌ ~ZmBE &
A) Write chemical equation of Finkelstein reaction.
B) Why aryl halides are less reactive towards nucleophilic substitution reactions?
Explain.
C) Arrange the following alkyl halides in increasing order of their reactivity
towards SN2 reaction.
CH3–CH2–Cl, (CH3)2CH–Cl, (CH3)3C–Cl
D) Draw the orbital diagram of CH3Cl.
OR
A) Write chemical equation of Wurtz-Fittig reaction.
B) The reaction of alkyl chloride with aqueous KOH leads to the formation of
alcohols but in presence of alcoholic KOH, alkenes are major products.
Explain.
C) Arrange the following halogen derivatives in increasing order of their
reactivity towards nucleophilic substitution reactions.

R–Cl, –Cl, –CH2–Cl

D) Draw a labelled diagram of laboratory method of preparation of chloroform.



SS–41–Chem. 1333

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