JEE Main 2026 Apr 4 Shift 2 — Chemistry

The correct order of total number of atoms present in

(A) 2 moles of cyclohexane

(B) 684 g of sucrose

(C) 90.8 L of dihydrogen at STP

is:

The species having identical radii according to the Bohr's theory are:

A. $\mathrm{H}$ (first orbit)

B. $\mathrm{He^+}$ (first orbit)

C. $\mathrm{He^+}$ (Second orbit)

D. $\mathrm{Li^{2+}}$ (first orbit)

E. $\mathrm{Be^{3+}}$ (Second orbit)

Choose the correct answer from the options given below:

Which of the following pictorial diagram most correctly represents the $\pi^*$ ($\pi$-antibonding) molecular orbital if the internuclear axis is taken to be in the z-direction $\left(\xrightarrow{\text{z-axis}}\right)$?

At 27 °C, 0.1 M, 1 L $\mathrm{K_4[Fe(CN)_6]}$ aqueous solution and 0.1 M, 1 L $\mathrm{FeCl_3}$ aqueous solution are placed in a container separated by a semi permeable membrane AB. Assume complete dissociation of both the solutes. Which of the following statement is correct?

a container divided by a semi-permeable membrane AB; left compartment: 0.1 M, 1 L $\mathrm{K_4[Fe(CN)_6

}$, side 'x'; right compartment: 0.1 M, 1 L$\mathrm{FeCl_3}$, side 'y']*

20 mL of a solution of acetic acid required 28.4 mL of 0.1 M NaOH for its neutralization. A solution (X) was prepared by mixing 20 mL of the above acetic acid and 14.2 mL of 0.1 M NaOH solution. What is the pH of the solution (X)? ($\mathrm{p}K_a$ value of acetic acid is 4.75).

Match the LIST-I with LIST-II

List-I (Reaction)	List-II (Mechanism)
A. Williamson Synthesis	I. Electrophilic addition
B. Friedel Craft Reaction	II. Free radical substitution
C. Bromination of vinyl benzene	III. Nucleophilic substitution
D. Chlorination of toluene in light	IV. Electrophilic substitution

Choose the correct answer from the options given below:

The $1^{\text{st}}$ ionization enthalpy for Mg is +737 kJ/mol. The most probable estimated value of $2^{\text{nd}}$ ionization enthalpy of Mg is ________.

The electronegativity of a group 13 element 'E' is same as that of Ge (on Pauling scale and upto one decimal point). The CORRECT statements about $\mathrm{E^{3+}}$ are

A. It can act as a reducing agent.

B. It can act as an oxidizing agent.

C. $\mathrm{E^{3+}}$ is more stable than $\mathrm{E^{+}}$.

D. The standard electrode potential value for $\mathrm{E^{3+}/E}$ is positive.

Choose the correct answer from the options given below:

Pairs of elements with the same number of electrons in their respective 4f orbital are

[Atomic number: Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72]

A. (Eu and Gd)

B. (Dy and Ho)

C. (Yb and Hf)

D. (Lu and Tm)

Choose the correct answer from the options given below:

Consider the metal complexes $\mathrm{[Ni(en)_3]^{2+}}$ (A), $\mathrm{[NiCl_4]^{2-}}$ (B) and $\mathrm{[Ni(NH_3)_6]^{2+}}$ (C). Choose the CORRECT option by considering the number of unpaired electrons present in (A), (B) and (C) respectively and the order of frequency of absorption.

Consider the following molecules/species:

(x) cyclohepta-2,4,6-trien-1-one (tropone); (y) $\mathrm{(CH_3)_2C{=}O}$ (propan-2-one); (z) $\mathrm{CH_3{-}C({=}O){-}O^{(-)}}$ (acetate ion)

The correct order of carbon – oxygen double bond length is :

Consider $|x|$ is the difference in oxidation states of Mn in highest manganese fluoride and highest manganese oxide. The ions with $|x|$ number of unpaired electrons from the following are:

A. $\mathrm{Sc^{3+}}$

B. $\mathrm{Zn^{2+}}$

C. $\mathrm{V^{2+}}$

D. $\mathrm{Fe^{2+}}$

E. $\mathrm{Co^{2+}}$

Choose the correct answer from the options given below:

Consider the given graph showing variation of reactant concentration with time.

Three different reactions were started with identical initial concentration of reactants. Which of the following statement is correct?

graph of [R

(mol L$^{-1}$) vs t/s, all three curves starting from $[R]_0$; curve 1 decreases linearly, curves 2 and 3 decay exponentially with curve 3 falling fastest]*

styrene (vinylbenzene, $\mathrm{C_6H_5{-}CH{=}CH_2}$), labelled (X)

$\mathrm{(X)} \xrightarrow[\begin{array}{l}\text{(ii) } \mathrm{NaNH_2} \text{ excess} \\ \text{(iii) } \mathrm{CH_3I} \\ \text{(iv) } \mathrm{H_2,\ Na/NH_3}\ (l)\end{array}]{\text{(i) } \mathrm{Br_2\,/\,CHCl_3}}$ Major Product (Y)

Compound (X) is subjected to the sequence of reactions as shown above. Molar mass of the major product (Y) formed is ______________ $\mathrm{g\ mol^{-1}}$.

(Given molar mass in $\mathrm{g\ mol^{-1}}$ C: 12, H: 1, O: 16)

The following structures are

two wedge-dash structures of a carbon centre bearing Br (up), Cl, $\mathrm{CH_3}$ and Me, drawn as mirror images of each other — i.e. the same carbon carries both a $\mathrm{CH_3}$ and a Me group

The descending order of acidity among the following compounds is:

structures — A. phenol; B. 4-nitrophenol ($\mathrm{O_2N}$ substituted phenol); C. 4-methoxyphenol ($\mathrm{H_3CO}$ substituted phenol); D. 4-nitrobenzoic acid ($\mathrm{O_2N}$ substituted benzoic acid); E. benzoic acid

Choose the correct answer from the options given below:

The strongest conjugate acid will result from:

A D-aldotetrose on oxidation with concentrated $\mathrm{HNO_3}$ resulted in optically inactive dicarboxylic acid. The structure of the D-aldotetrose is:

Among $\mathrm{Fe^{3+}}$, $\mathrm{Pb^{2+}}$, $\mathrm{Cu^{2+}}$ and $\mathrm{Mn^{2+}}$, identify the one that gets precipitated out while passing $\mathrm{H_2S}$ in presence of $\mathrm{NH_4OH}$ as group reagent. The highest possible oxidation state of the corresponding metal is

Match the LIST-I with LIST-II

List-I (Compound)	List-II (Test)
A. [structure: cyclohexanol]	I. Hinsberg's reagent test
B. [structure: cyclohexanamine (cyclohexyl-$\mathrm{NH_2}$)]	II. Phthalein dye test
C. [structure: cyclohexanecarbaldehyde (cyclohexyl-CHO)]	III. Lucas test
D. [structure: phenol]	IV. Tollen's test

Choose the correct answer from the options given below:

If 3.365 g of ethanol ($l$) is burnt completely in a bomb calorimeter at 298.15 K, the heat produced is 99.472 kJ. The $|\Delta H_f^\circ|$ of ethanol at 298.15 K is ____________ $\times 10^{2}\ \mathrm{kJ\ mol^{-1}}$. (Nearest integer)

Given: Standard enthalpy for combustion of graphite $= -393.5\ \mathrm{kJ\ mol^{-1}}$

Standard enthalpy of formation of water (l) $= -285.8\ \mathrm{kJ\ mol^{-1}}$

Molar mass in $\mathrm{g\ mol^{-1}}$ of C, H, O are 12, 1 and 16 respectively

For the following reaction at 50 °C and at 2 atm pressure,

$\mathrm{2N_2O_5(g) \rightleftharpoons 2N_2O_4(g) + O_2(g)}$

$\mathrm{N_2O_5}$ is 50% dissociated.

The magnitude of standard free energy change at this temperature is $x$.

$x =$ ________ $\mathrm{J\ mol^{-1}}$ [Nearest integer].

Given : R = 8.314 $\mathrm{J\ mol^{-1}\ K^{-1}}$, log 2 = 0.30, log 3 = 0.48, ln10 = 2.303, °C + 273 = K

An electrochemical cell, consist of the following two redox couples, $\mathrm{M^{x+}(aq)/M(s)}$ $[E^{\ominus}_{red} = +0.15\ \mathrm{V}]$ and $\mathrm{Fe^{3+}(aq)/Fe(s)}$ $[E^{\ominus}_{red} = -0.036\ \mathrm{V}]$. The cell EMF ($E_{cell}$) is recorded to be 0.2057 V. If the reaction quotient of the electrochemical reaction is found to be $10^{-2}$, then the value of $x$ is ____________. (Nearest integer)

[Given : M is a p-block metal and $\dfrac{2.303RT}{F} = 0.059\ \mathrm{V}$]

For a first order reaction A $\rightarrow$ B

t/min	[A]/M
0	0.6500
x	0.0650
20	0.00065

$x =$ ____________ min. (Nearest integer)

In sulphur estimation, $2.0 \times 10^{-3}$ mol of an organic compound (X) (molar mass 76 $\mathrm{g\ mol^{-1}}$) gave 0.4813 g of barium sulphate (molar mass 233 $\mathrm{g\ mol^{-1}}$). The percentage of sulphur in the compound (X) is ___________ $\times 10^{-1}$ % (Nearest integer)