JEE Main 2021 (Online) 18th March Morning Shift
JEE Main / 30 questions
2026Thu, Mar 18, 2021 3:30 AM30 PYQs
1Aldehydes Ketones And Carboxylic Acids
Considering the above chemical reaction, identify the product "X" :
MCQ+4 / -12021
2Aldehydes Ketones And Carboxylic Acids
Consider the above chemical reaction and identify product "A"
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3Basics Of Organic Chemistry
Compound with molecular formula C3H6O can show :
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4Biomolecules
A non-reducing sugar "A" hydrolyses to give two reducing mono saccharides. Sugar A is
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5Chemical Bonding And Molecular Structure
AX is a covalent diatomic molecule where A and X are second row elements of periodic table. Based on Molecular orbital theory, the bond order of AX is 2.5. The total number of electrons in AX is __________. (Round off to the Nearest Integer...
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6Chemical Kinetics And Nuclear Chemistry
2NO(g) + Cl2(g) \(\rightleftharpoons\) 2NOCl(s) This reaction was studied at \(-\)10\(^\circ\) and the following data was obtained
Run
\({[NO]_0}\)
\({[C{l_2}]_0}\)
\({r_0}\)
1
0.10
0.10
0.18
...
Run
\({[NO]_0}\)
\({[C{l_2}]_0}\)
\({r_0}\)
1
0.10
0.10
0.18
...
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7Chemistry In Everyday Life
Match the list - I with list - II
List - I(Class of Drug)
List - II(Example)
(a)
Antacid
(i)
Novestrol
(b)
Artificial sweetener
(ii)
Cimetidine
(c)
Antifertil...
List - I(Class of Drug)
List - II(Example)
(a)
Antacid
(i)
Novestrol
(b)
Artificial sweetener
(ii)
Cimetidine
(c)
Antifertil...
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8Compounds Containing Nitrogen
Considering the above reaction, X and Y respectively are :
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9Coordination Compounds
The total number of unpaired electrons present in the complex K3[Cr(oxalate)3] is _____________.
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10Coordination Compounds
The correct structures of trans-[NiBr2(PPh3)2] and meridonial-[Co(NH3)3(NO2)3], respectively, are
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11D And F Block Elements
Match List - I with List - II
List - I
List - II
(a)
Chlorophyll
(i)
Ruthenium
(b)
Vitamin-\({B_{12}}\)
(ii)
Platinum
(c)
Anticancer drug
(iii)
Cobalt...
List - I
List - II
(a)
Chlorophyll
(i)
Ruthenium
(b)
Vitamin-\({B_{12}}\)
(ii)
Platinum
(c)
Anticancer drug
(iii)
Cobalt...
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12Electrochemistry
For the reaction 2Fe3+(aq) + 2I\(-\)(aq) \(\to\) 2Fe2+(aq) + I2(s) the magnitude of the standard molar Gibbs free energy change, \(\Delta\)rG\(_m^o\) = \(-\) ___________ kJ (Round off to the Nearest Integer).$$\left[ {\matrix{
{E_{F{e^...
{E_{F{e^...
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13Environmental Chemistry
The statements that are TRUE :(A) Methane leads to both global warming and photochemical smog(B) Methane is generated from paddy fields(C) Methane is a stronger global warming gas than CO2(D) Methane is a part of reducing smogChoose the mos...
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14Haloalkanes And Haloarenes
Reaction of Grignard reagent, C2H5MgBr with C8H8O followed by hydrolysis gives compound "A" which reacts instantly with Lucas reagent to give compound B, C10H13Cl. The Compound B is :
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15Hydrocarbons
Match List - I with List - II :List - I (Chemicals)(a) Alcoholic potassium hydroxide(b) Pd/BaSO4(c) BHC (Benzene hexachloride)(d) PolyacetyleneList - II (Use / Preparation / Constituent)(i) Electrodes in batteries(ii) Obtained by addition r...
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16Ionic Equilibrium
Given below are two statements : One is labelled as Assertion A and the other labelled as reason RAssertion A : During the boiling of water having temporary hardness, Mg(HCO3)2 is converted to MgCO3.Reason R : The solubility product of Mg(O...
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17Ionic Equilibrium
In order to prepare a buffer solution of pH 5.74, sodium acetate is added to acetic acid. If the concentration of acetic acid in the buffer is 1.0 M, the concentration of sodium acetate in the buffer is ___________ M. (Round off to the Near...
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18Isolation Of Elements
The chemical that is added to reduce the melting point of the reaction mixture during the extraction of aluminium is :
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19P Block Elements
Match List - I with List - II
List - I(process)
List - II(catalyst)
(a)
Deacron's process
(i)
ZSM-5
(b)
Contact process
(ii)
\(CuC{l_2}\)
(c)
Cracking of hydr...
List - I(process)
List - II(catalyst)
(a)
Deacron's process
(i)
ZSM-5
(b)
Contact process
(ii)
\(CuC{l_2}\)
(c)
Cracking of hydr...
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20P Block Elements
The number of ionisable hydrogens present in the product obtained from a reaction of phosphorus trichloride and phosphonic acid is :
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21Periodic Table And Periodicity
The ionic radius of Na+ ions is 1.02 \(\mathop A\limits^o\). The ionic radii (in \(\mathop A\limits^o\)) of Mg2+ and Al3+, respectively, are
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22Practical Organic Chemistry
Reagent, 1-napthylamine and sulphanilic acid in acetic acid is used for the detection of
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23S Block Elements
Match List - I with List - II
List - I
List - II
(a)
\(Ca{(OCl)_2}\)
(i)
Antacid
(b)
\(CaS{O_4}.{1 \over 2}{H_2}O\)
(ii)
Cement
(c)
\(CaO\)
(iii)
Blea...
List - I
List - II
(a)
\(Ca{(OCl)_2}\)
(i)
Antacid
(b)
\(CaS{O_4}.{1 \over 2}{H_2}O\)
(ii)
Cement
(c)
\(CaO\)
(iii)
Blea...
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24Solid State
In a binary compound, atoms of element A form a hcp structure and those of element M occupy 2/3 of the tetrahedral voids of the hcp structure. The formula of the binary compound is :
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25Solutions
2 molal solution of a weak acid HA has a freezing point of 3.885\(^\circ\)C. The degree of dissociation of this acid is ___________ \(\times\) 10\(-\)3. (Round off to the Nearest Integer).[Given : Molal depression constant of water = 1.85 K...
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26Some Basic Concepts Of Chemistry
Complete combustion of 3g of ethane gives x \(\times\) 1022 molecules of water. The value of x is __________. (Round off to the Nearest Integer). [Use : NA = 6.023 \(\times\) 1023; Atomic masses in u : C : 12.0; O : 16.0; H : 1.0]
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27Some Basic Concepts Of Chemistry
A reaction of 0.1 mole of Benzylamine with bromomethane gave 23 g of Benzyl trimethyl ammonium bromide. The number of moles of bromomethane consumed in this reaction are n \(\times\) 10\(-\)1, when n = __________. (Round off to the Nearest ...
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28Some Basic Concepts Of Chemistry
__________ grams of 3-Hydroxy propanal (MW = 74) must be dehydrated to produce 7.8 g of acrolein (MW = 56) (C3H4O) if the percentage yield is 64. (Round off to the Nearest Integer).[Given : Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u ...
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29Structure Of Atom
A certain orbital has no angular nodes and two radial nodes. The orbital is :
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30Thermodynamics
For the reaction C2H6 \(\to\) C2H4 + H2the reaction enthalpy \(\Delta\)rH = __________ kJ mol\(-\)1. (Round off to the Nearest Integer).[ Given : Bond enthalpies in kJ mol\(-\)1 : C-C : 347, C = C : 611; C-H : 414, H-H : 436 ]
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