List of top Questions asked in JEE Main

Bond line formula of HOCH(CN)$_2$ is:

Given below are two statements:
Statement (I) : Oxygen being the first member of group 16 exhibits only –2 oxidation state.
Statement (II) : Down the group 16 stability of +4 oxidation state decreases and +6 oxidation state increases.
In the light of the above statements, choose the most appropriate answer from the options given below:

The incorrect statement regarding conformations of ethane is:

Identity the incorrect pair from the following:

$\text{The number of non-polar molecules from the following is \_\_\_\_\_\_.} \\ \text{HF, H}_2\text{O, SO}_2, \, \text{H}_2, \, \text{CO}_2, \, \text{CH}_4, \, \text{NH}_3, \, \text{HCl, CHCl}_3, \, \text{BF}_3$

$\text{Time required for completion of 99.9\% of a first order reaction is \_\_\_\_\_\_ times of half life } (t_{1/2}) \text{ of the reaction.}$

$\text{The Spin only magnetic moment value of square planar complex } [\text{Pt(NH}_3\text{)}_2\text{Cl(NH}_2\text{CH}_3\text{)}]\text{Cl is } \_\_\_\_\_\_ \text{ B.M. (Nearest integer)} \\ \text{(Given atomic number for Pt = 78)}$

$\text{For a certain thermochemical reaction } \text{M} \rightarrow \text{N at } T = 400 \, \text{K}, \, \Delta H^\circ = 77.2 \, \text{kJ mol}^{-1}, \, \Delta S = 122 \, \text{JK}^{-1}, \\ \text{log equilibrium constant (log K) is } - \_\_\_\_\_ \times 10^{-1}.$

$\text{The hydrogen electrode is dipped in a solution of pH = 3 at } 25^{\circ}\text{C. The potential of the electrode will be } -\_\_\_\_\_ \times 10^{-2} \text{ V.}$
$\left( \frac{2.303RT}{F} = 0.059 \, \text{V} \right)$

$9.3 \, \text{g of aniline is subjected to reaction with excess of acetic anhydride to prepare acetanilide. The mass of acetanilide produced if the reaction is 100\% completed is } \_\_\_\_\_ \times 10^{-1} \, \text{g.} \\ \text{(Given molar mass in g mol}^{-1}\text{) N: 14, O: 16, C: 12, H: 1}$

Total number of compounds with Chiral carbon atoms from following is ________.

$\text{CH}_3 - \text{CH}_2 - \text{CH(NO}_2\text{) - COOH} \\ \text{CH}_3 - \text{CH}_2 - \text{CHBr - CH}_2 - \text{CH}_3 \\ \text{CH}_3 - \text{CH(I) - CH}_2 - \text{NO}_2 \\ \text{CH}_3 - \text{CH}_2 - \text{CH(OH) - CH}_2\text{OH} \\$

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: The first ionisation enthalpy decreases across a period.
Reason R: The increasing nuclear charge outweighs the shielding across the period.
In the light of the above statements, choose the most appropriate from the options given below:

Match List I with List II:

List I (Substances)	List II (Element Present)
(A) Ziegler catalyst	(I) Rhodium
(B) Blood Pigment	(II) Cobalt
(C) Wilkinson catalyst	(III) Iron
(D) Vitamin B12	(IV) Titanium

Choose the correct answer from the options given below :

In chromyl chloride test for confirmation of Cl^-, a yellow solution is obtained. Acidification of the solution and addition of amyl alcohol and 10% H₂O₂​ turns organic layer blue indicating formation of chromium pentoxide. The oxidation state of chromium in that is

The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is

The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is:

The arenium ion which is not involved in the bromination of Aniline is .

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : Aryl halides cannot be prepared by replacement of hydroxyl group of phenol by halogen atom.
Reason R : Phenols react with halogen acids violently. In the light of the above statements.
Choose the most appropriate from the options given below:

Identify product A and product B :

How many of the following vitamins are stored in Human Body?
A, B, C, D, E, K?

Calculate the Molarity of a Solution having density = \(1.5\) \(g/ml\). \(\%(w/w)\) of Solute is \(36\%\) and Molecular weight of Solute is \(36\) \(g/mol\)

Given below are two statements:
Statement-I: The gas liberated on warming a salt with dil H₂SO₄, turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion.
Statement-II: In statement-I the colour of paper turns black because of formation of lead sulphite. In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are the two statements: one is labelled as Assertion (A) and the other is labeled as Reason (R).
Assertion (A): There is a considerable increase in covalent radius from N to P. However from As to Bi only a small increase in covalent radius is observed.
Reason (R): covalent and ionic radii in a particular oxidation state increases down the group.
In the light of the above statement, choose the most appropriate answer from the options given below:

Example of vinylic halide is

Structure of 4-Methylpent-2-enal is