List of top Questions asked in JEE Main

A compound (\( x \)) with molar mass \( 108 \, \text{g mol}^{-1} \) undergoes acetylation to give a product with molar mass \( 192 \, \text{g mol}^{-1} \). The number of amino groups in the compound (\( x \)) is ______.

Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is _______.

Number of moles of \( H^+ \) ions required by 1 mole of \( MnO_4^- \) to oxidise oxalate ion to \( CO_2 \) is ____.

In the reaction of potassium dichromate, potassium chloride and sulfuric acid (conc.), the oxidation state of the chromium in the product is (+)_______.

The values of conductivity of some materials at \( 298.15 \, \text{K} \) in \( \text{S m}^{-1} \) are:
\( 2.1 \times 10^3, \, 1.0 \times 10^{-16}, \, 1.2 \times 10^1, \, 3.91, \, 1.5 \times 10^{-2}, \, 1 \times 10^{-7}, \, 1.0 \times 10^3 \).
The number of conductors among the materials is ______.

From the vitamins \( A, \, B_1, \, B_6, \, B_{12}, \, C, \, D, \, E, \, \text{and} \, K \), the number of vitamins that can be stored in our body is ______.

What pressure (bar) of \( \text{H}_2 \) would be required to make the emf of a hydrogen electrode zero in pure water at \( 25^\circ \text{C} \)?

Given below are two statements:
Statement (I) : A Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities.
Statement (II) : Blood is naturally occurring buffer solution whose pH is maintained by $H_2CO_3/HCO_3^-$ concentrations.
In the light of the above statements, choose the correct answer from the options given below.

Given below are two statements:
Statement (I) : All the following compounds react with p-toluenesulfonyl chloride.
$C_6H_5NH_2 \quad      (C_6H_5)_2NH                \quad (C_6H_5)_3N$
Statement (II) : Their products in the above reaction are soluble in aqueous NaOH.
In the light of the above statements, choose the correct answer from the options given below.

The emf of cell Tl$\vert^{Tl^+}_{_{(0.001M)}}\vert^{Cu^{2+}}_{_{(0.01M)}}$Cu is 0.83 V at 298 K. It could be increased by:

Identify the correct statements about p-block elements and their compounds.
(A) Non metals have higher electronegativity than metals.
(B) Non metals have lower ionisation enthalpy than metals.
(C) Compounds formed between highly reactive nonmetals and highly reactive metals are generally ionic.
(D) The non-metal oxides are generally basic in nature.
(E) The metal oxides are generally acidic or neutral in nature.

Given below are two statements :
Statement (I) : Kjeldahl method is applicable to estimate nitrogen in pyridine.
Statement (II) : The nitrogen present in pyridine can easily be converted into ammonium sulphate in Kjeldahl method.
In the light of the above statements, choose the correct answer from the options given below.

The reaction;$\frac{1}{2}H_{2(g)} + AgCl_{(s)} \rightarrow H^+_{(aq)} + Cl^-_{(aq)} + Ag_{(s)}$ occurs in which of the following galvanic cell:

Given below are two statements:
Statement (I) : Fusion of MnO$_2$ with KOH and an oxidising agent gives dark green K$_2$MnO$_4$.
Statement (II) : Manganate ion on electrolytic oxidation in alkaline medium gives permanganate ion.
In the light of the above statements, choose the correct answer from the options given below.

Match List-I with List-II.

List-I (Complex ion)	List-II (Spin only magnetic moment in B.M.)
(A) [Cr(NH$_3$)$_6$]$^{3+}$	(I) 4.90
(B) [NiCl$_4$]$^{2-}$	(II) 3.87
(C) [CoF$_6$]$^{3-}$	(III) 0.0
(D) [Ni(CN)$_4$]$^{2-}$	(IV) 2.83

Choose the correct answer from the options given below:

$\Delta_{vap}H^\circ$ for water is $+40.49 \, \text{kJ mol}^{-1}$ at 1 bar and $100^\circ\text{C}$. Change in internal energy for this vaporisation under same condition is .............. kJ mol$^{-1}$. (Integer answer)
(Given R = 8.3 J K$^{-1}$ mol$^{-1}$)

Number of molecules having bond order 2 from the following molecule is ...................
$C_2, O_2, Be_2, Li_2, Ne_2, N_2, He_2$

Total number of optically active compounds from the following is _______.

The total number of carbon atoms present in tyrosine, an amino acid, is _______.

Two moles of benzaldehyde and one mole of acetone under alkaline conditions using aqueous NaOH after heating gives $x$ as the major product. The number of $\pi$ bonds in the product $x$ is ................

Total number of aromatic compounds among the following compounds is _______.

Total number of unpaired electrons in the complex ion [Co(NH$_3$)$_6$]$^{3+}$ and [NiCl$_4$]$^{2-}$ is

Wavenumber for a radiation having $5800 \, \mathring{A}$ wavelength is $x \times 10 \, \text{cm}^{-1}$. The value of $x$ is _________

A solution is prepared by adding 1 mole ethyl alcohol in 9 mole water. The mass percent of solute in the solution is ___________ (Integer Answer)
(Given : Molar mass in g mol$^{-1}$ Ethyl alcohol : 46, water : 18)

Given below are two statements:
Statement I:

IUPAC name of Compound A is 4-chloro-1, 3-dinitrobenzene.
Statement II:

IUPAC name of Compound B is 4-ethyl-2-methylaniline.
In the light of the above statements, choose the most appropriate answer from the options given below: