JEE Main 2021 (Online) 26th February Morning Shift
JEE Main / 30 questions
2026Fri, Feb 26, 2021 3:30 AM30 PYQs
1Alcohols Phenols And Ethers
Given below are two statements : Statement I : o-Nitrophenol is steam volatile due to intramolecular hydrogen bonding.Statement II : o-Nitrophenol has high melting due to hydrogen bonding.In the light of the above statements, choose the mos...
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2Alcohols Phenols And Ethers
Identify the major products A and B respectively in the following reactions of phenol :
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3Alcohols Phenols And Ethers
B reacts with Hydroxyl amine but does not give Tollen's test. Identify A and B.
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4Basics Of Organic Chemistry
Given below are two statements :Statement I : A mixture of chloroform and aniline can be separated by simple distillation.Statement II : When separating aniline from a mixture of aniline and water by steam distillation aniline boils below i...
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5Biomolecules
Which of the following vitamin is helpful in delaying the blood clotting?
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6Chemical Bonding And Molecular Structure
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.Assertion A : Dipole-dipole interactions are the only non-covalent interactions, resulting in hydrogen bond formation.Reason R : Fluorine ...
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7Chemical Equilibrium
A homogeneous ideal gaseous reaction \(A{B_{2(g)}} \rightleftharpoons {A_{(g)}} + 2{B_{(g)}}\) is carried out in a 25 litre flask at 27\(^\circ\)C. The initial amount of AB2 was 1 mole and the equilibrium pressure was 1.9 atm. The value of ...
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8Compounds Containing Nitrogen
An amine on reaction with benzensulphonyl chloride produces a compound insoluble in alkaline solution. This amine can be prepared by ammonolysis of ethyl chloride. The correct structure of amine is :
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9Coordination Compounds
Number of bridging CO ligands in [Mn2(CO)10] is __________.
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10D And F Block Elements
Which one of the following lanthanoids does not form MO2? [M is lanthanoid metal]
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11Electrochemistry
Consider the following reaction\(MnO_4^ - + 8{H^ + } + 5{e^ - } \to M{n^{ + 2}} + 4{H_2}O,{E^o} = 1.51V\).The quantity of electricity required in Faraday to reduce five moles of \(MnO_4^ -\) is ___________. (Integer answer)
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12Electrochemistry
Compound A used as a strong oxidizing agent is amphoteric in nature. It is the part of lead storage batteries. Compound A is :
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13Environmental Chemistry
The presence of ozone in troposphere :
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14Gaseous State
A certain gas obeys P(Vm \(-\) b) = RT. The value of \({\left( {{{\partial Z} \over {\partial P}}} \right)_T}\) is \({{xb} \over {RT}}\). The value of x is _________. (Integer answer) (Z : compressibility factor)
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15Gaseous State
3.12 g of oxygen is adsorbed on 1.2 g of platinum metal. The volume of oxygen adsorbed per gram of the adsorbent at 1 atm and 300 K in L is __________.[R = 0.0821 L atm K\(-\)1mol\(-\)1]
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16Haloalkanes And Haloarenes
For the given reactionWhat is 'A'?
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17Haloalkanes And Haloarenes
For the given reaction :What is 'A'?
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18Hydrogen
Statements about heavy water are given below :A. Heavy water is used in exchange reactions for the study of reaction mechanisms.B. Heavy water is prepared by exhaustive electrolysis of water.(C) Heavy water has higher boiling point than ord...
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19Isolation Of Elements
Match List - I with List - II.
List - I (Ore)
List - II (Element Present)
(a)
Kernite
(i)
Tin
(b)
Cassiterite
(ii)
Boron
(c)
Calamine
(iii)
Fluorine
...
List - I (Ore)
List - II (Element Present)
(a)
Kernite
(i)
Tin
(b)
Cassiterite
(ii)
Boron
(c)
Calamine
(iii)
Fluorine
...
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20P Block Elements
On treating a compound with warm dil. H2SO4, gas X is evolved which turns K2Cr2O7 paper acidified with dil. H2SO4 to a green compound Y. X and Y respectively are :
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21P Block Elements
Find A, B and C in the following reactions :\(N{H_3} + A + C{O_2} \to {(N{H_4})_2}C{O_3}\)\({(N{H_4})_2}C{O_3} + {H_2}O + B \to N{H_4}HC{O_3}\)\(N{H_4}HC{O_3} + NaCl \to N{H_4}Cl + C\)
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22Periodic Table And Periodicity
Match List - I with List - II.
List I Electronic configuration
List II \({\Delta _i}H\) in kJ \(mo{l^{ - 1}}\)
(a)
\(1{s^2}2{s^2}\)
(i)
801
(b)
\(1{s^2}2{s^2}2{p^4}\)
(ii)
...
List I Electronic configuration
List II \({\Delta _i}H\) in kJ \(mo{l^{ - 1}}\)
(a)
\(1{s^2}2{s^2}\)
(i)
801
(b)
\(1{s^2}2{s^2}2{p^4}\)
(ii)
...
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23Polymers
The structure of Neoprene is :
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24Practical Organic Chemistry
Which of the following is 'a' FALSE statement ?
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25Redox Reactions
Dichromate ion is treated with base, the oxidation number of Cr in the product formed is ___________.
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26Solutions
224 mL of SO2(g) at 298 K and 1 atm is passed through 100 mL of 0.1 M NaOH solution. The non-volatile solute produced is dissolved in 36g of water. The lowering of vapour pressure of solution (assuming the solution in dilute) (P$$_{({H_2}O)...
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27Some Basic Concepts Of Chemistry
The number of significant figures in 50000.020 \(\times\) 10\(-\)3 is _____________.
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28Structure Of Atom
The orbital having two radial as well as two angular nodes is :
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29Thermodynamics
An exothermic reaction X \(\to\) Y has an activation energy 30 kJ mol\(-\)1. If energy change \(\Delta\)E during the reaction is \(-\)20 kJ, then the activation energy for the reverse reaction in kJ is ___________. (Integer answer)
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30Thermodynamics
For a chemical reaction A + B ⇌ C + D(\({\Delta _r}{H^\Theta }\) = 80 kJ mol\(-\)1) the entropy change \({\Delta _r}{S^\Theta }\) depends on the temperature T (in K) as \({\Delta _r}{S^\Theta }\) = 2T (J K\(-\)1mol\(-\)1).Minimum temperatur...
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