2 (chemistry) jee main 2015 (04-04-15) part-a : … · [ 2] (chemistry) jee main 2015 (04-04-15)...
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Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
[ 2 ] (CHEMISTRY) JEE MAIN 2015 (04-04-15)
PART-A : CHEMISTRY*1. Which of the following is the energy of a possible excited state of hydrogen ?
(1) – 6.8 eV (2) – 3.4 eV (3) + 6.8 eV (4) + 13.6 eVAns. (2)Sol. Energy of electron of Hydrogen atom
2
13.6 evn
Possible energy –13.6 , -3.4, -1.51, - 0.85, -1.541st excited state. Energy is -3.4
2. In the following sequences of reactions : 4 2 2
4
KMnO SOCl H /PdBaSO
Toluene A B C the product
C is :
(1) C6H5CH3 (2) C6H5CH2OH (3) C6H5CHO (4) C6H5COOHAns. (3)
Sol.
CH3
4KMnO
C –OH
2SOCl 2
4
H /PdBaSO
O
C –Cl
O
C –H
O
(A) (B) (C)
*3. Which compound would give 5-keto-2-methyl hexanal upon ozonolysis ?
(1)
CH3
CH3
(2)
CH3
CH3
(3)
CH3
H3C (4)
CH3
CH3
Ans. (1)
Sol.
CH3
CH3
3 2O / Zn/H O
O O
H
* Question from Syllabus of Class 11th
JEE MAIN 2015 (04-04-15) (CHEMISTRY) [ 3 ]
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
4. The ionic radii (in Å) of N3–, O2– and F– are respectively :(1) 1.36, 1.71 and 1.40 (2) 1.71, 1.40 and 1.36(3) 1.71, 1.36 and 1.40 (4) 1.36, 1.40 and 1.71
Ans. (2)
Sol. 3 2N ,O & F are isoelectronic species.
for isoelectronic species
1(Z / e)radius
order of ionic radius is 3 2N O F
5. The colour of KMnO4 is due to :(1) d – d transition(2) L M charge transfer transition
(3) – * transition
(4) M L charge transfer transitionAns. (2)
Sol. 4KMnO Purple colour
4 4KMnO K MnO
Mn
O
O O–O Colour of compound due to L M Charge transfer
6. Assertion : Nitrogen and Oxygen are the main components in the atmosphere but these do not react toform oxides of nitrogen.
Reason : The reaction between nitrogen and oxygen requires high temperature.(1) Both assertion and reason are correct, but the reason is not the correct explanation for the assertion.(2) The assertion is incorrect, but the reason is correct.(3) Both the assertion and reason are incorrect.(4) Both assertion and reason are correct, and the reason is the correct explanation for the assertion.
Ans. (4)
Sol. 2N and 2O are highly stable at room temperature, so it has very high activation energy. It requires hightemperature to proceed.
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
[ 4 ] (CHEMISTRY) JEE MAIN 2015 (04-04-15)
7. Which of the following compounds is not an antacid ?
(1) Cimetidine (2) Phenelizine
(3) Ranitidine (4) Aluminium hydroxide
Ans. (2)
Sol. (1), (2), (3) Antacid and (2) Antidepressant. (Not an antacids)
8. In the context of the Hall-Heroult process for the extraction of Al, which of the following statements isfalse ?
(1) Al2O3 is mixed with CaF2 which lowers the melting point of the mixture and brings conductivity.
(2) Al3+ is reduced at the cathode to form Al.
(3) Na3AlF6 serves as the electrolyte.
(4) CO and CO2 are produced in this process.
Ans. (3)
9. Match the catalysts to the correct processes :
(A) TiCl3 (i) Wacker process
(B) PdCl2 (ii) Ziegler - Natta polymerization
(C) CuCl2 (iii) Contact process
(D) V2O5 (iv) Deacon’s process
(1) (A) - (ii), (B) - (i), (C) - (iv), (D) - (iii)
(2) (A) - (ii), (B) - (iii), (C) - (iv), (D) - (i)
(3) (A) - (iii), (B) - (i), (C) - (ii), (D) - (iv)
(4) (A) - (iii), (B) - (ii), (C) - (iv), (D) - (i)
Ans. (1)
Sol. 3TiCl Ziegler Natta Catalyst (Polymerisation)
2PdCl Wacker's Pr ocess (for oxidation of alkene to carbonyl compound)
2CuCl Deacon's Process (preparation of Chlorine)
2 5V O Contact Pr ocess (preparation of 2 4H SO )
JEE MAIN 2015 (04-04-15) (CHEMISTRY) [ 5 ]
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
10. In the reaction :
NH2
CH3
2NaNO / HCl CuCN/ KCN20–5 C
D E N
; the product E is :
(1) H C3 CH3 (2)
CN
CH3
(3)
CH3
(4)
COOH
CH3
Ans. (2)
Sol.
(E)
NH2
CH3
2o
NaNO /HCl0 5 C
CH3
2N Cl
CuCN/KCN
CH3
CN
11. Which polymer is used in the manufacture of paints and lacquers ?(1) Glyptal (2) Polypropene (3) Poly vinyl chloride (4) Bakelite
Ans. (1)Sol. Glyptal is used in the manufacture of paints and Lacquers.12. The number of geometric isomers that can exist for square planar [Pt (Cl) (py) (NH3) (NH2OH)]+ is
(py = pyridine) :(1) 3 (2) 4 (3) 6 (4) 2
Ans. (1)
Sol. Complex is nM abcd type
geometrical isomers = 3.Here a, b, c & d are monodentate ligand.
I
+ba
d c
M
II
+ca
d b
M
III
+ba
c d
M
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[ 6 ] (CHEMISTRY) JEE MAIN 2015 (04-04-15)
13. Higher order (>3) reactions are rare due to :(1) increase in entropy and activation energy as more molecules are involved.(2) shifting of equilibrium towards reactants due to elastic collisions(3) loss of active species on collision(4) low probability of simultaneous collision of all the reacting species
Ans. (4)Sol. Chances of collision of more than 3 molecules at an instant are very low.14. Which among the following is the most reactive ?
(1) Br2 (2) I2 (3) ICI (4) Cl2Ans. (3)Sol. Inter-halogen compounds are more reactive than hologen in polar solvent.15. 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) 63.5 g (2) 2 g (3) 127 g (4) 0 g
Ans. (1)Sol. 2F of electricity deposit 2 equivalent of Cu
Cu 2e Cu 2 equivalent = 1 Mole Cu = 63.5 gm
*16. 3 g of activated charcoal was added to 50 ml. acetic acid solution (0.06 N) in a flask. After an hour it wasfiltered and the strength of the filtrate was found to be 0.042 N. The amount of acetic acid adsorbed (pergram of charcoal) is :(1) 36 mg (2) 42 mg (3) 54 mg (4) 18 mg
Ans. (4)
Sol. Meq of 3CH COOH 50 0.6 = 3
Meq of remaining 3CH COOH 50 .042 = 2.100
Meq of 3CH COOH adsorbed 3 2.1 = 0.9
0.9 60 .054 gm 54 m g1000
Per gm of Charcoal 54 18mg3
17. The synthesis of alkyl fluorides in best accomplished by :(1) Sandmeyer’s reaction (2) Finkelstein reaction(3) Swarts reaction (4) Free radical fluorination
Ans. (3)
Sol. Alkyl flouride is best prepared by using R Cl, R Br
by metal flouride like 2 2 2 3AgF, CoF , Hg F , SbF
AgF
(Cl,Br ) ( Cl,Br )R x R F AgX
JEE MAIN 2015 (04-04-15) (CHEMISTRY) [ 7 ]
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
*18. 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 by the resin when expressed in mole pergram resin ?
(1)1
206 (2)2
309
(3)1
412(4)
1103
Ans. (3)
Sol. 2 8 7 3 8 7 3 2C H SO Na C H SO Ca
mole of Ca 1
mole of Ca per gm of resin 1 1
2 206 412
mol
19. Which of the vitamins given below is water soluble ?
(1) Vitamin D (2) Vitamin E (3) Vitamin K (4) Vitamin C
Ans. (4)
Sol. Vitamin B & C are water soluble.
*20. The intermolecular interaction that is dependent on the inverse cube of distance between the moleculesis :
(1) ion-dipole interaction (2) London force
(3) hydrogen bond (4) ion-ion interaction
Ans. (3)
Sol. Order of interactions are
cation & anion interaction 21fr
dipole-dipole interaction 31fr
Vander waal force of attraction 61fr
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
[ 8 ] (CHEMISTRY) JEE MAIN 2015 (04-04-15)
*21. 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 86.6 kJ/mol at 298 K. What is the standard free energyof formation of NO2(g) at 298 K ? (Kp = 1.6 × 1012)
(1) 86600 + R(298) ln (1.6 × 1012) (2) 12n 1.6 10
86600R(298)
l
(3) 0.5 [2 × 86,600 – R(298)] ln (1.6 × 1012)] (4) R(298) ln (1.6 × 1012) – 86600Ans. (3)
Sol. 2 22NO O 2NO �
opG 2x 2 86600 RTlnK
12x .86600 0.5R 298ln 1.6 10
12x 0.5 2 86600 R 298ln 1.6 10
22. Which of the following compounds is not colored yellow ?(1) K3[Co(NO2)6] (2) (NH4)3 [As (Mo3 O10)](3) BaCrO4 (4) Zn2[Fe(CN)6]
Ans. (4)
Sol. 3 2 6K Co NO Yellow
4 3 3 10 4(NH ) As Mo O Yellow
4BaCrO Yellow
2 6Zn Fe CN White
*23. In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg of AgBr. Thepercentage of bromine in the compound is : (at. mass of Ag = 108; Br = 80)(1) 36 (2) 48 (3) 60 (4) 24
Ans. (4)
Sol.sample
80 wt.of AgBr% of Br 100188 w
80 144 100 24%
188 250
JEE MAIN 2015 (04-04-15) (CHEMISTRY) [ 9 ]
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24. Sodium metal crystallizes in a body centred cubic lattice with a unit cell edge of 4.29 Å. The radius ofsodium atom is approximately :
(1) 3.22 Å (2) 5.72 Å (3) 0.93 Å (4) 1.86 Å
Ans. (4)
Sol. oa 4.29A
o3a 1.732 4.29r A4 4
o1.86A
25. Which of the following compounds will exhibit geometrical isomerism ?
(1) 3 - Phenyl - 1- butene (2) 2 - Phenyl - 1 - butene
(3) 1, 1 - Diphenyl - 1 - propane (4) 1 - Phenyl - 2 - butene
Ans. (4)
Sol.Ph
1– Phenyl –2– butene.
This compound has two different groups at each end of double bond
26. The vapour pressure of acetone at 20°C is 185 torr. When 1.2 g of a non-volatile substance was dissolvedin 100 g of acetone at 20°C, its vapour pressure was 183 torr. The molar mass (g mol–1) of the substanceis :
(1) 64 (2) 128 (3) 488 (4) 32
Ans. (1)
Sol.o
s
o ssolute
o
P 185 torrW 1.2gmP 183P P X
P
1.2 /M 185 1831.2 100 185M 58
1.2 58 2M 100 185
1.2 58 185M100 2
64
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
[ 1 0 ] (CHEMISTRY) JEE MAIN 2015 (04-04-15)
*27. From the following statements regarding H2O2, choose the in correct statement :
(1) It decomposes on exposure to light
(2) It has to be stored in plastic or wax lined glass bottles in dark
(3) It has to be kept away from dust
(4) It can act only as an oxidizing agent
Ans. (4)
Sol. 2 2H O can act oxidising as well as reducing agent.
As oxidising nature As reducing nature
2 2 2 2(H O O H O O )
2 2 2H O H O O 2 2 2H O 2H O 2e
28. Which one of the following alkaline earth metal sulphates has its hydration enthalpy greater than itslattice enthalpy ?
(1) BeSO4 (2) BaSO4 (3) SrSO4 (4) CaSO4
Ans. (1)
Sol. order of solubility
4 4 4 4BeSO CaSO SrSO BaSO
Hence,
hydration 4 Lattice 4H BeSO H BeSO
JEE MAIN 2015 (04-04-15) (CHEMISTRY) [ 1 1 ]
Mentors Eduserv: Plot No.-136/137, Parus Lok Complex, Boring Road Crossing,Patna-1, Ph. No. : 0612-3223680 / 81
*29. The standard Gibbs energy change at 300 K for the reaction 2A � � ��� � �� B + C is 2494.2 J. At a given time,
the composition of the reaction mixture is [A] , [B] 22
and 1[C] .2
The reaction proceeds in the :
[R = 8.314 J/K/mol, e = 2.718](1) reverse direction because Q > Kc (2) forward direction because Q < Kc(3) reverse direction because Q < Kc (4) forward direction because Q > Kc
Ans. (1)
Sol. 2A B C�
2 2
12B C 2Q 41A2
cG G RT nQ l
2494.2 8.314 300 n4 l
G 0( ve)
So, reverse reaction, and Q > Kc*30. Which one has the highest boiling point ?
(1) Ne (2) Kr (3) Xe (4) HeAns. (3)Sol. Boling point Molar mass
Hence, Xe has the maximum boiling point
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