2018 JEE Chemistry Solved paper

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Previous Year Paper Chemistry - 2018
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Chemistry JEE 2018
Exam Year 2018
Study, Assignments, Solved Previous Year Papers .
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Multiple Choice Questions 1. An alkali is
titrated against an acid with methyl orange as
indicator, which of the following is a correct
combination?
Base Acid End Point
Strong Strong Pink to colourless
Base Acid End Point
Weak Strong Colourless to pink
Base Acid End Point
Strong Strong Pinkish Red to Yellow
Base Acid End Point
Weak Strong Yellow to Pinkish Red
Answer 2. The predominant form of histamine
present in human blood is (pKa, Histidine 6.0)
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Chemistry JEE 2018
Exam Year 2018
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Answer 3. Which of the following lines correctly
show the temperature dependence of equilibrium
constant K, for an exothermic reaction?
A and D A and B B and C C and D Answer 4. The
combustion of benzene (l) gives CO2(g) and
H2O(l). Given that heat of combustion of benzene
at constant volume is 3263.9 kJ mol1 at 250C
the heat of combustion (in kJ mol1) of benzene
at constant pressure will be (R 8.314 JK1
mol1) 3267.6
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Chemistry JEE 2018
Exam Year 2018
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• 4152.6
• 452.46
• 3260
• Answer
• The ratio of mass percent of C and H of an
  organic compound (CXHYOZ) is 6 1. If one
  molecule of the above compound (CXHYOZ) contains
  half as much oxygen as required to burn one
  molecule of compound CXHY completely to CO2 and
  H2O. The empirical formula of compound CXHYOZ is
• C2H4O3 C3H6O3 C2H4O C3H4O2
• Answer
• Which of the following are Lewis acids? BCl3 and
  AlCl3
• PH3 and BCl3 AlCl3 and SiCl4 PH3 and SiCl4
• Answer
• According to molecular orbital theory, which of
  the following will not be a viable molecule?
  H22-
• He22 He2 H2-
• Answer
• Which of the following compounds contain(s) no
  covalent bond(s)? KCl, PH3, O2, B2H6, H2SO4
• KCl, B2H6
• KCl, B2H6, PH3 KCl, H2SO4
• KCl Answer
• Total number of lone pair of electrons in I - ion
  is

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Chemistry JEE 2018
Exam Year 2018
Study, Assignments, Solved Previous Year Papers .
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• 3
• 6
• 9
• Answer
• Hydrogen peroxide oxidises Fe(CN)64- to
  Fe(CN)63- in acidic medium but reduces
  Fe(CN)63- to Fe(CN)64- in alkaline medium.
  The other products formed are, respectively
• H -
• 2O and (H2O OH )
• (H2O O2) and H2O
• (H O O ) and (H O OH-)
• 2 2 2
• H2O and (H2O O2)
• Answer
• When metal M is treated with NaOH, a white
  gelatinous precipitate X is obtained, which is
  soluble in excess of NaOH. Compound X when
  heated strongly gives an oxide which is used in
  chromatography as an adsorbent. The metal M is
• Fe Zn Ca Al
• Answer
• The recommended concentration of ?uoride ion in
  drinking water is up to 1 ppm as ?uoride ion is
  required to make teeth enamel harder by
  converting 3Ca3 (PO4)2.Ca(OH)2 to
• 3Ca(OH)2. CaF2 CaF2

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Chemistry JEE 2018
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• oxygen released can completely burn 27.66 g of
  diborane? (Atomic weight of B 10.8 u)
• 1.6 hours
• 6.4 hours
• 0.8 hours
• 3.2 hours Answer
• Consider the following reaction and statements
  Co(NH3)4Br2 Br- ? Co(NH3)3Br3 NH3
• Two isomers are produced if the reactant complex
  ion is a cis-isomer
• Two isomers are produced if the reactant complex
  ion is a trans-isomer
• Only one isomer is produced if the reactant
  complex ion is a trans-isomer
• Only one isomer is produced if the reactant
  complex ion is a cis isomer The correct
  statements are
• (II) and (IV)
• (I) and (II)
• (I) and (III)
• (III) and (IV) Answer
• An aqueous solution contains an unknown
  concentration of Ba2. When 50 mL of a 1 M
  solution of Na SO is
• 2 4

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Chemistry JEE 2018
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• Answer
• The trans-alkenes are formed by the reduction of
  alkynes with Sn - HCl
• H2 Pd/C, BaSO4 NaBH4
• Na/liq. NH3 Answer
• Which type of defect has the presence of
  cations in the interstitial sites?
• Metal de?ciency defect Schottky defect Vacancy
  defect Frenkel defect
• Answer
• An aqueous solution contains 0.10 M H2S and 0.20
  M HCl. If the equilibrium constants for the
  formation of HS from H 7 2- 13 2-
• 2S is 1.0 x10 and that of S from HS ions is
  1.2 x 10 then the concentration of S ions in
• aqueous solution is
• 5 x 10-19
• 5 x 10-8
• 3 x 1020
• 6 x 10-21
• Answer
• The oxidation states of Cr in Cr(H2O)6Cl3,Cr(C6
  H6)2, and K2Cr(CN)2 (O)2(O2)(NH3) respectively
  are

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Chemistry JEE 2018
Exam Year 2018
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• Answer
• Glucose on prolonged heating with HI gives
  6-iodohexanal
• n-Hexane 1-Hexene
• Hexanoic acid Answer
• The increasing order of basicity of the following
  compounds is

(d) lt (b) lt (a) lt (c) (a) lt (b) lt (c) lt (d) (b) lt
(a) lt (c) lt (d) (b) lt (a) lt (d) lt (c) Answer 25.
Phenol reacts with methyl chloroformate in the
presence of NaOH to form product A. A reacts with
Br2 to
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Chemistry JEE 2018
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form product B. A and B are respectively
Answer 26. The major product formed in the
following reaction is
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Chemistry JEE 2018
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Answer 27. Phenol on treatment with CO2 in the
presence of NaOH followed by acidi?cation
produces compound X as the major product. X on
treatment with (CH3CO)2O in the presence of
catalytic amount of H2SO4 produces
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Chemistry JEE 2018
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Answer 28. The major product of the following
reaction is,
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Chemistry JEE 2018
Exam Year 2018
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• Answer
• The compound that does not produce nitrogen gas
  by the thermal decomposition is (NH4)2SO4
• Ba(N3)2 (NH4)2Cr2O7 NH4NO2
• Answer
• Which of the following salts is the most basic in
  aqueous solution? Pb(CH3COO)2
• Al(CN)3 CH3COOK
• FeCl3 Answer

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