JEE Main 2026 (Online) 24th January Evening Shift

\(\text { From the following, how many compounds contain at least one secondary alcohol?}\)

Choose the correct answer from the options given below :

The unsaturated ether on acidic hydrolysis produces carbonyl compounds as shown below :-

Based on this, predict the solution/reagent that will help to distinguish "P" and "Q" obtained in the following reaction :-

Given below are two statements :
Statement I : Cross aldol condensation between two different aldehydes will always produce four different products.
Statement II : When semicarbazide reacts with a mixture of benzaldehyde and acetophenone un...

Grignard reagent $\mathrm{RMgBr}(\mathrm{P})$ reacts with water and forms a gas $(\mathrm{Q})$. One gram of Q occupies $1.4 \mathrm{dm}^3$ at STP. (P) on reaction with dry ice in dry ether followed by $\mathrm{H}_3 \mathrm{O}^{+}$forms a co...

Given below are two statements :
Statement I : There are several conformers for n -butane. Out of those conformers,

Statement II : As the dihedral angle increases, torsional strain decreases from (X) to $(\mathrm{Y})$.
In the light of the ...

Find out the statements which are not true.
A. Resonating structures with more number of covalent bonds and lesser charge separation are more stable.
B. In electromeric effect, an unsaturated system shows +E effect with nucleophile and -E e...

The number of possible tripeptides formed involving alanine (ala), glycine (gly) and valine (val), where no amino acid has been used more than once is:

Pair of species among the following having same bond order as well as paramagnetic character will be-

Consider the following gaseous equilibrium in a closed container of volume ' $V$ ' at $\mathrm{T}(\mathrm{K})$.
\(\mathrm{P}_2(\mathrm{~g})+\mathrm{Q}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{PQ}(\mathrm{~g})\)
2 moles each of $\mathrm...

The half-life of ${ }^{65} \mathrm{Zn}$ is 245 days. After $x$ days, $75 \%$ of original activity remained. The value of $x$ in days is $\_\_\_\_$ . (Nearest integer)
(Given: $\log 3=0.4771$ and $\log 2=0.3010$ )

A student has planned to prepare acetanilide from aniline using acetic anhydride.
The student has started from 9.3 g of aniline. However, the student has managed to obtain 11 g of dry acetanilide.
The % yield of this reaction is :-

Given below are two statements :
Statement I : The dipole moment of R-CN is greater than R-NC and R-NC can

Statement II : R-CN hydrolyses under acidic medium to produce a compound which on treatment with $\mathrm{SOCl}_2$, followed by the ...

\(\text { The wavelength of light absorbed for the following complexes are in the order }\)

A chromium complex with a formula $\mathrm{CrCl}_3 \cdot 6 \mathrm{H}_2 \mathrm{O}$ has a spin only magnetic moment value of 3.87 BM and its solution conductivity corresponds to $1: 2$ electrolyte. 2.75 g of the complex solution was initial...

Molar conductivity of a weak acid HQ of concentration 0.18 M was found to be $1 / 30$ of the molar conductivity of another weak acid HZ with concentration of 0.02 M . If $\lambda^{\circ} \mathrm{Q}^{-}$happened to be equal with $\lambda^{\c...

Choose the INCORRECT statement

" X " is an oxoanion of the lightest element of group 7 (in the periodic table). The metal is in +6 oxidation state in " X ". The color of the potassium salt of X is

The correct order of $\mathrm{C}, \mathrm{N}, \mathrm{O}$ and F in terms of second ionisation potential is

One mole of $\mathrm{Cl}_2(\mathrm{~g})$ was passed into 2 L of cold 2 M KOH solution. After the reaction, the concentrations of $\mathrm{Cl}^{-}, \mathrm{ClO}^{-}$and $\mathrm{OH}^{-}$are respectively (assume volume remains constant)

In the Group analysis of cations, $\mathrm{Ba}^{2+} $ & $\mathrm{Ca}^{2+}$ are precipitated respectively as

At 298 K , the mole percentage of $\mathrm{N}_2(\mathrm{~g})$ in air is $80 \%$. Water is in equilibrium with air at a pressure of 10 atm . What is the mole fraction of $\mathrm{N}_2(\mathrm{~g})$ in water at 298 K ? $\left(\mathrm{K}_{\mat...

Two liquids A and B form an ideal solution at temperature T K . At T K , the vapour pressures of pure A and B are 55 and $15 \mathrm{kN} \mathrm{m}^{-2}$ respectively. What is the mole fraction of A in solution of A and B in equilibrium wit...

0.25 g of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of $\mathrm{CaCl}_2$ tube and potash tube at the end of the experiment. The amount was found to...

The wavelength of spectral line obtained in the spectrum of $\mathrm{Li}^{2+}$ ion, when the transition takes place between two levels whose sum is 4 and difference is 2 , is

The heat of atomisation of methane and ethane are ' x ' $\mathrm{kJ} \mathrm{mol}^{-1}$ and ' y ' $\mathrm{kJ} \mathrm{mol}^{-1}$ respectively. The longest wavelength ( $\lambda$ ) of light capable of breaking the $\mathrm{C}-\mathrm{C}$ bo...