JEE Main 2021 (Online) 16th March Morning Shift
JEE Main / 30 questions
2026Tue, Mar 16, 2021 3:30 AM30 PYQs
1Aldehydes Ketones And Carboxylic Acids
The product ''P'' in the above reaction is :
MCQ+4 / -12021
2Aldehydes Ketones And Carboxylic Acids
Assertion A : Enol form of acetone [CH3COCH3] exists in < 0.1% quantity. However, the enol form of acetyl acetone [CH3COCH2OCCH3] exists in approximately 15% quantity.Reason R : Enol form of acetyl acetone is stabilized by intramolecular hy...
MCQ+4 / -12021
3Basics Of Organic Chemistry
Among the following, the aromatic compounds are :Choose the correct answer from the following options :
MCQ+4 / -12021
4Basics Of Organic Chemistry
In chromotography technique, the purification of compound is independent of :
MCQ+4 / -12021
5Biomolecules
Which among the following pairs of Vitamins is stored in our body relatively for longer duration?
MCQ+4 / -12021
6Chemical Bonding And Molecular Structure
Given below are two statements : one is labeled as Assertion A and the other is labelled as Reason R :Assertion A : The H\(-\)O\(-\)H bond angle in water molecule is 104.5\(^\circ\).Reason R : The lone pair - lone pair repulsion of electron...
MCQ+4 / -12021
7Chemical Equilibrium
For the reaction \(A(g) \rightleftharpoons B(g)\) at 495 K, \(\Delta\)rG\(^\circ\) = \(-\)9.478 kJ mol\(-\)1.If we start the reaction in a closed container at 495 K with 22 millimoles of A, the amount of B in the equilibrium mixture is ____...
INTEGER+4 / -12021
8Chemical Kinetics And Nuclear Chemistry
The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is 1.0 \(\times\) 10\(-\)3 s\(-\)1 and the activation energy Ea = 11.488 kJ mol\(-\)1, the rate constant at 200 K is ____________ $...
INTEGER+4 / -12021
9Chemistry In Everyday Life
The functions of antihistamine are :
MCQ+4 / -12021
10Compounds Containing Nitrogen
Which of the following reactions DOES NOT involve Hoffmann bromamide degradation?
MCQ+4 / -12021
11Compounds Containing Nitrogen
In the above chemical reaction, intermediate ''X'' and reagent/condition ''A'' are :
MCQ+4 / -12021
12Coordination Compounds
The equivalents of ethylene diamine required to replace the neutral ligands from the coordination sphere of the trans-complex of CoCl3 . 4NH3 is _________. (Round off to the Nearest Integer).
INTEGER+4 / -12021
13D And F Block Elements
Given below are two statements :Statement I : The Eo value for Ce4+ / Ce3+ is + 1.74 V.Statement II : Ce is more stable in Ce4+ state than Ce3+ state.In the light of the above statements, choose the most appropriate answer from the options ...
MCQ+4 / -12021
14D And F Block Elements
Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R :Assertion A : Size of Bk3+ ion is less than Np3+ ion.Reason R : The above is a consequence of the lanthanoid contraction.In the light of t...
MCQ+4 / -12021
15Environmental Chemistry
The type of pollution that gets increased during the day time and in the presence of O3 is :
MCQ+4 / -12021
16Haloalkanes And Haloarenes
The products ''A'' and ''B'' formed in above reactions are :
MCQ+4 / -12021
17Hydrocarbons
Which of the following is Lindlar catalyst?
MCQ+4 / -12021
18Hydrogen
Given below are two statements :Statement I : H2O2 can act as both oxidising and reducing agent in basic medium.Statement II : In the hydrogen economy, the energy is transmitted in the form of dihydrogen.In the light of the above statements...
MCQ+4 / -12021
19Ionic Equilibrium
Two salts A2X and MX have the same value of solubility product of 4.0 \(\times\) 10\(-\)12. The ratio of their molar solubilities i.e. \({{S({A_2}X)} \over {S(MX)}}\) = __________. (Round off to the Nearest Integer)
INTEGER+4 / -12021
20Isolation Of Elements
The process that involves the removal of sulphur from the ores is :
MCQ+4 / -12021
21P Block Elements
A group of 15 element, which is a metal and forms a hydride with strongest reducing power among group 15 hydrides. The element is :
MCQ+4 / -12021
22P Block Elements
Match List - I with List - II :
List - IIndustrial process
List - IIApplication
(a)
Haber's process
(i)
\(HN{O_3}\) synthesis
(b)
Ostwald's process
(ii)
Aluminium extractio...
List - IIndustrial process
List - IIApplication
(a)
Haber's process
(i)
\(HN{O_3}\) synthesis
(b)
Ostwald's process
(ii)
Aluminium extractio...
MCQ+4 / -12021
23P Block Elements
Match List - I with List - II :
List - I Name of oxo acid
List - II Oxidation state of 'P'
(a)
Hypophosphorous acid
(i)
+5
(b)
Orthophosphoric acid
(ii)
+4
(c)
...
List - I Name of oxo acid
List - II Oxidation state of 'P'
(a)
Hypophosphorous acid
(i)
+5
(b)
Orthophosphoric acid
(ii)
+4
(c)
...
MCQ+4 / -12021
24S Block Elements
Given below are two statements :Statement I : Both CaCl2 . 6H2O and MgCl2 . 8H2O undergo dehydration on heating.Statement II : BeO is amphoteric whereas the oxides of other elements in the same group are acidic.In the light of the above sta...
MCQ+4 / -12021
25Solid State
A certain element crystallises in a bcc lattice of unit cell edge length 27\(\mathop A\limits^o\). If the same element under the same conditions crystallises in the fcc lattice, the edge length of the unit cel in \(\mathop A\limits^o\) wi...
INTEGER+4 / -12021
26Solutions
AB2 is 10% dissociated in water to A2+ and B\(-\). The boiling point of a 10.0 molal aqueous solution of AB2 is __________\(^\circ\)C. (Round off to the Nearest Integer).[Given : Molal elevation constant of water Kb = 0.5 K kg mol\(-\)1 boi...
INTEGER+4 / -12021
27Some Basic Concepts Of Chemistry
A 6.50 molal solution of KOH (aq.) has a density of 1.89 g cm\(-\)3. The molarity of the solution is ____________ mol dm\(-\)3. (Round off to the Nearest Integer).[Atomic masses : K : 39.0 u; O : 16.0 u; H : 1.0 u]
INTEGER+4 / -12021
28Some Basic Concepts Of Chemistry
Complete combustion of 750 g of an organic compound provides 420 g of CO2 and 210 g of H2O. The percentage composition of carbon and hydrogen in organic compound is 15.3 and ___________ respectively. (Round off to the Nearest Integer).
INTEGER+4 / -12021
29Some Basic Concepts Of Chemistry
\(2MnO_4^ - + b{C_2}O_4^{2 - } + c{H^ + } \to xM{n^{2 + }} + yC{O_2} + z{H_2}O\)If the above equation is balanced with integer coefficients, the value of c is ___________. (Round off to the Nearest Integer).
INTEGER+4 / -12021
30Structure Of Atom
When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is _______\(\mathop A\limits^o\). (Round off to the Nearest Integer).[ Use : \(\sqrt 3\) = 1.73, h = 6.63 $$\times...
INTEGER+4 / -12021
