jee main chemistry solutions

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SOLUTION OF JEE MAIN. 2015IITians TAPASYA

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PART - C [CHEMISTRY] (CODE C)Q.61 The vapour pressure of acetone at 20oC is 185 torr. When1.2 g of a non-volatile substance was

dissolved in 100 g of acetone at 20oC, its vapour pressure was 183 torr. The molar mass (g mol1)of the substance is :

(1) 488 (2) 32 (3) 64 (4) 128

Sol. (3) oS acetone acetoneP P X

0

0

10058183 185 M 64g/mol100 1.2

58 M

Q.62 3 g of activated charcoal was added to 50 mL of acetic acid solution (0.06N) in a flask. After an hour

it was filtered and the strength of the filtrate was found to be adsorbed (per gram of charcoal) is :

(1) 54 mg (2) 18 mg (3) 36 mg (4) 42 mg

Sol. (2) 50 0.06 50 0.042 meq of CH3COOH absorbed. 3 2.1 meq 0.9meq 0.9 60 mg 54mg

Hence, 3g Charcoal 54 mg CH3COOH

1g ----------------- 18 mg CH3COOH 18 mg CH3COOH / gm charcoal.

Q.63 Which of the following is the energy of a possible excited state of hydrogen ?

(1) + 6.8 eV (2) 13.6 eV (3) 6.8 eV (4) 3.4 eV



[ 2 ]IITians TAPASYA...IITians creating IITiansSol. (4)

2

n 221E 13.6eV n 2, E 3.4eVn

Q.64 Which among the following is the most reactive ?

(1) ICI (2) CI2 (3) Br2 (4) I2

Sol. (1) Most reactive ICI I CI due to polarity..Q.65 Which polymer is used in the manufacture of paints and lacquers ?

(1) Poly vinyl chloride (2) Bakelite (3) Glyptal (4) PolypropeneSol. (3) Glyptal NCERT- Pg. 436 Table 15.1Q.66 The molecular formula of a commercial resin used for exchanging ions in water softening is

C8H7SO3Na (Mol. wt. 206). What would be the maximum uptake of Ca2+ ions byh the resin whenexpressed in mole per gram resin ?(1) 1/412 (2) 1/103 (3) 1/206 (4) 2/309

Sol. (1) 28 7 3 8 7 3 22 C H SO Na Ca C H SO Ca 2 mole resin 1 mole Ca2+

2

2

1 1mole resin mole Ca / gm resin206 412

1 mole Ca / gm resin412

Q.67 In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg ofAgBr. The percentage of bromine in the compoind is :(at mass Ag = 108 ; Br = 108)(1) 60 (2) 24 (3) 36 (4) 48

Sol. (2) Ag Br 188 g AgBr 80 g Br

108 + 80 = 188 141 mg80 141 mg Br

188

80 141188% Br 100% 24%

250

Q.68 Assertion : Nitrogen and Oxygen are the main components in the atmosphere but these do notreact to form oxides of nitrogen.Reason : The reaction between nitrogen and oxygen of nitrogen and oxygen requires hightemperature.(1) Both the assertion and reason are incorrect(2) Both assertion and reason are correct, and the reason are correct explanation for the assertion.



[ 3 ]IITians TAPASYA...IITians creating IITians(3) Both assertion and reason are correct, but the reason is not the correct explanation

for the assertion.(4) The assertion is incorrect, but the reason is correct.

Sol. (1) Assertion and Reason are both correct and Reason is the correct explanation of assertion.N2 and O2 react at higher temp.

Q.69 The following reaction is performed at 298 K.

2 22NO g O g 2NO g The standard free energy of formation of NO(g) is 86.6kJ/mol at 298 K. What is the standard free

energy of formation of NO2(g) at 298 K? 12pK 1.6 10 (1) l 120.5[2 86600 R(298) n(1.6 10 )] (2) l 12R(298) n(1.6 10 ) 86600

(3) l 1286600 R(298) n(1.6 10 ) (4) l12n(1.6 10 )86600

R(298)

Sol. (1)

2 2

o o oReaction f 2 f

oP f 2

o 12f 2

2NO g O g 2NO g

G 2 G NO g 2 G NO g

RT ln K 2 G NO g 2 86600

G NO g 0.5 2 86600 R 298 ln 1.6 10

Q.70 Which one of the following alkaline earth metal sulphate has its hydration entalpy greater than itslattice enthalpy ?(1) SrSO4 (2) CaSO4 (3) BeSO4 (4) BaSO4

Sol. (3) BeSO4 (most soluble)Q.71 The number of geometrical isomers that can exist for square planar [Pt (CI) (py) (NH3) (NH2OH)]+

is (py = pyridine) :(1) 6 (2) 2 (3) 3 (4) 4

Sol. (3)

CI Pt

NH3

NH OH2

Py

CI Pt

NH3 NH OH2

Py CI Pt

NH3

NH OH2

Py

[M(abcd)]Q.72 The synthesis of alkyl fluorides is best accomplished by :

(1) Swarts reaction (2) Free radical fluorination(3) Sandmeyers reaction (4) Finkelstein reaction

Sol. (1) Swart reactionQ.73 The intermolecular interaction that is dependent on the inverse cube of distance between the



[ 4 ]IITians TAPASYA...IITians creating IITiansmolecules is :(1) hydrogen bond (2) ion-ion interaction (3) ion-dipole interaction (4) London force

Sol. (3) Ion-dipole interactionQ.74 In the context of the Hall-Heroult process for the extraction of AI, which of the following statement

is false ?(1) Na3AIF6 serves as the electrolyte(2) CO and CO2 are produced in this process(3) Al2O3 is mixed with CaF2 which lowers the melting point of the mixture and brings conductivity(4) Al3+ is reduced at the cathode to form AI

Sol. (3) Al2O3 is mixed with CaF2 which lowers the M.P of the mixture and brings conductivity is false,(Na3 AlF6) is used.

Q.75 Which of the following compounds will exhibit geometrical isomerism ?(1) 1,1 - Diphenyl - 1 propane (2) 1 - Phenyl - 2 - butene(3) 3 - Phenyl - 1 - butene (4) 2 - Phenyl -1 - butene

Sol. (2) I - phenyl - but - 2 -ene

C == CH

CH3

H

C == C

H

CH3H

(Cis) (trans)

Q.76 The ionic radii (inoA ) of N3, O2 and F are respectively :

(1) 1.71, 1.36 and 1.40 (2) 1.36, 1.40 and 1.71(3) 1.36, 1.71 and 1.40 (4) 1.71, 1.40 and 1.366

Sol. (4) For isoelectronic species, size 1Atomicnumber

(N3 > P2 > F) N3

1.71 1.40 1.36 O3 F--

Q.77 From the following statements regarding H2O2, choose the incorrect statement :(1) It has to be kept away from dust(2) It can act only as an oxidizing agent(3) It decomposes on exposure to light(4) It has to be stored in plastic or wax lined glass bottle in dark

Sol. (2) It can act as oxidising agent only, is false. H2O2 acts as an oxidant as well as reductant.Q.78 Higher order (> 3) reactions are rare due to :

(1) loss of active species on collision(2) low probability of simultaneous collision of all the reacting species



[ 5 ]IITians TAPASYA...IITians creating IITians(3) increase in entropy and activation energy as more molecules are involved(4) shifting of equilibrium towards reactants due to elastic collision.

Sol. (2) Low probability of simultaneous collision of all the reacting species.Q.79 Match the catalyst to the correct processes :

Catalyst Process(A) TiCI3 (i) Wacker process(B) PdCI2 (ii) Ziegler-Natta polymerization(C) CuCI2 (iii) Contact process(D) V2O5 (iv) Deacons process(1) (A) - (iii), (B) - (i), (C) - (ii), (D) - (iv) (2) (A) - (iii), (B) - (ii), (C) - (iv), (D) - (i)(3) (A) - (ii), (B) - (i), (C) - (iv), (D) - (iii) (4) (A) - (ii), (B) - (iii), (C) - (iv), (D) - (i)

Sol. (3) Ticl3 - Ziegler - Natto PolymerisationPdcl2 - Wacker processCucl2 - Deacons processV2O5 - Contact process

[Hint : V2O5 is used in contact process] only one option is correct.Q.80 Which one has the highest boiling point ?

(1) Xe (2) He (3) Ne (4) KrSol. (1) Xe is the heaviest has highest B.pt.

Q.81 In the reaction

NH2

CH3

2o

NaNO / HCI CuCN/ KCN20 5 C

D E N

the product E is :

(1)

CH3

(2)

COOH

CH3

(3) CH3H C3 (4)

CN

CH3

Sol. (4)

NH2

CH3

2o

NaNO HCI0 5 C

N CI2

CH3

+

CuCN/KCN

C N

CH3

+ N2



[ 6 ]IITians TAPASYA...IITians creating IITiansQ.82 Which of the following compounds is not colored yellow ?

(1) BaCrO4 (2) Zn2 [Fe(CN)6 ] (3) K3 [Co(NO2)6] (4) (NH4)3[As (Mo3 O10)4]Sol. (2) Zn2 [Fe (CN)6 ] is bluish - white.Q.83 Sodium metal crystallizes in a body centred cubic lattice with a unit cell edge of 4.29

oA . The

radius of sodium atom is approximately :(1)

o0.93 A (2)

o1.86 A (3)

o3.22A (4)

o5.72A

Sol. (2)o o3 34r 3 a, r a x4.29 A 1.86 A.

4 4 for (BCC)

Q.84 The standard Gibbs energy change at 300 K for the reaction 2A B C is 2494.2 J. At agiven time, the composition of the reaction mixture is [A] = 1/2, [B] = 2 and [C] = 1/2. The reactionproceeds in the : [R = 8.314 J/K/mol, e = 2.718](1) reverse direction because Q > KC (2) forward direction becasue Q > KC(3) reverse direction because Q > KC (4) forward direction because Q < KC

Sol. (3) loG RT nK 2494.2 = (8.31 x 300) lnK ,

lnK = 1, K = 1e

c 2 2

12xB C 2Q 2A 1

2

Q > K, hence (reverse)

Q.85 Which compound would give 5-keto-2-methyl hexanal upon ozonolysis ?

(1)

CH3H C3

(2)

CH3CH3

(3)

CH3

CH3

(4)

CH3

CH3

Sol. (3) C C C C C CC

3

2

OZn/H O A

C CC C

C C

C

CH3

CH3



[ 7 ]IITians TAPASYA...IITians creating IITiansQ.86 Which of the following compounds is not an antacid ?

(1) Ranitidine (2) Aluminium hydroxide (3) Cimetidine (4) PhenelzineSol. (4) Phenelzine is not an antacid.Q.87 In the following sequence of reactions :

4 2 2

4

KMnO SOCI H / PdBaSOToluene A B C , the product C is :

(1) C6H5CHO (2) C6H5COOH (3) C6H5CH3 (4) C6H5CH2OH

Sol. (1)

CH3

4KMnOCOOH

2SOCl

C

O

CI 24

Pd / HBaSO

C

O

H

[Rosenmund reduction]Q.88 Which of the following vitamins given below is water soluble ?

(1) Vitamin K (2) Vitamin C (3) Vitamin D (4) Vitamin EAns. (2) Vitamin C is soluble in water. (NCERT)Q.89 The color of KMnO4 is due to :

(1) * transition (2) M L charge transfer transition(3) d d transition (4) L M charge transfer transition

Sol. (4) L M charge transfer O2 ions transfer charge to Mn2+ which causes purple colour..Q.90 Two Faraday of electricity is passed through a solution of CuSO4.The mass of copper deposited

at the cathode is :(at. mass of Cu = 63.5 amu)(1) 127 g (2) 0 g (3) 63.5 g (4) 2 g

Sol. (3) No. of gm-eg = No. of faradays

2 WCu 2e Cu 2 W 63.5 g63.5 / 2

jee main chemistry solutions

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