JEE Main 2026 Apr 2 Shift 2 — Chemistry

The ratio of mass percentage (w/w) of C : H in a hydrocarbon is 12 : 1. It has two carbon atoms. The weight (in g) of $\mathrm{CO_2}$(g) formed when 3.38 g of this hydrocarbon is completely burnt in oxygen is :

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

The first and second ionization constants of a weak dibasic acid $\mathrm{H_2A}$ are $8.1 \times 10^{-8}$ and $1.0 \times 10^{-13}$ respectively. 0.1 mol of $\mathrm{H_2A}$ was dissolved in 1 L of 0.1 M HCl solution. The concentration of $\mathrm{HA^-}$ in the resultant solution is :

$\mathrm{SF_4}$ is isostructural with :

A. $\mathrm{BrF_4^{\ominus}}$

B. $\mathrm{CH_4}$

C. $\mathrm{IF_4^{\oplus}}$

D. $\mathrm{XeF_4}$

E. $\mathrm{XeO_2F_2}$

Choose the correct answer from the options given below :

Gas 'A' undergoes change from state 'X' to state 'Y'. In this process, the heat absorbed and work done by the gas is 10 J and 18 J respectively. Now gas is brought back to state 'X' by another process during which 6 J of heat is evolved. In the reverse process of 'Y' to 'X',

Solution A is prepared by dissolving 1 g of a protein (molar mass = 50000 g mol$^{-1}$) in 0.5 L of water at 300 K. Its osmotic pressure is $x$ bar. Solution B is made by dissolving 2 g of same protein in 1 L of water at 300 K. Osmotic pressure of solution B is $y$ bar. Entire solution of A is mixed with entire solution of B at same temperature. The osmotic pressure of resultant solution is $z$ bar. $x$, $y$ and $z$ respectively are :

(R = 0.083 L bar mol$^{-1}$ K$^{-1}$)

At 25°C, 20.0 mL of 0.2 M weak monoprotic acid HX is titrated against 0.2 M NaOH. The pH of the solution (a) at the start of the titration (when NaOH has not been added) and (b) when 10 mL of NaOH is added respectively, are :

Given : $K_a = 5 \times 10^{-4}$

$\mathrm{p}K_a = 3.3$

$\alpha << 1$

(a) $\quad$ (b)

Consider the reaction $\mathrm{aX \rightarrow bY}$, for which the rate constant at 30°C is $1 \times 10^{-3}$ mol$^{-1}$ L s$^{-1}$. Which of the following statements are true ?

A. When concentration of 'X' is increased to four times, the rate of reaction becomes 16 times.

B. The reaction is a second order reaction.

C. The half-life period is independent of the concentration of X.

D. Decomposition of $\mathrm{N_2O_5}$ is an example of the above reaction.

E.

straight-line increasing plot of $\ln \frac{[R_0

}{[R]}$ versus time]* is valid for the above reaction.

Choose the correct answer from the options given below :

The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is :

Given below are two statements :

Statement I : The second ionization enthalpy of B, Al and Ga is in the order of B > Al > Ga.

Statement II : The correct order in terms of first ionization enthalpy is Si < Ge < Pb < Sn.

In the light of the above statements, choose the correct answer from the options given below :

Given below are two statements :

Statement I : Among Zn, Mn, Sc and Cu, the energy required to remove the third valence electron is highest for Zn and lowest for Sc.

Statement II : The correct order of the following complexes in terms of CFSE is $\mathrm{[Co(H_2O)_6]^{2+}} < \mathrm{[Co(H_2O)_6]^{3+}} < \mathrm{[Co(en)_3]^{3+}}$.

In the light of the above statements, choose the correct answer from the options given below :

Which of the following complexes will show coordination isomerism ?

A. $\mathrm{[Ag(NH_3)_2][Ag(CN)_2]}$

B. $\mathrm{[Co(NH_3)_6][Cr(CN)_6]}$

C. $\mathrm{[Co(NH_3)_6][Co(CN)_6]}$

D. $\mathrm{[Fe(NH_3)_6][Co(CN)_6]}$

E. $\mathrm{[Co(NH_3)_6][Fe(CN)_6]}$

Choose the correct answer from the options given below :

Complete combustion of X g of an organic compound gave 0.25 g of $\mathrm{CO_2}$ and 0.12 g of $\mathrm{H_2O}$. If the % of carbon is 25% and of hydrogen is 4.89%, then X = _____ $\times 10^{-3}$ g. (Nearest integer)

(Molar mass of C, H and O are 12, 1 and 16 g mol$^{-1}$ respectively.)

Given below are two statements :

Statement I : In $\mathrm{O_2N{-}C_6H_4{-}\overset{\oplus}{C}H{-}C_6H_4{-}OCH_3}$

benzylic carbocation bearing a 4-nitrophenyl ring and a 4-methoxyphenyl ring

, the carbocation is stabilised by +R effect of $\mathrm{-OCH_3}$ group.

Statement II : In $\mathrm{O_2N{-}C_6H_4{-}\overset{\ominus}{C}H{-}C_6H_4{-}OCH_3}$

the corresponding benzylic carbanion

, the carbanion is stabilised by $-$R effect of $\mathrm{-NO_2}$ group.

In the light of the above statements, choose the correct answer from the options given below :

The compound (X) on

(i) on heating in the presence of anhydrous $\mathrm{AlCl_3}$ and HCl gas gives 2,4-dimethyl pentane

(ii) aromatization gives toluene and

(iii) cyclisation gives methyl cyclohexane

The correct name of compound (X) is :

Correct statements regarding alkyl halides (R$-$X) among the following are :

A. Alcohol being less polar solvent as compared to water, alcoholic KOH favours elimination reaction with R$-$X.

B. Order of reactivity towards $\mathrm{S_N1}$ mechanism is $\mathrm{C_6H_5{-}CH_2{-}Cl > C_6H_5{-}CHCl{-}C_6H_5}$.

C. Non substituted aryl halides exhibit properties similar to alkyl halides.

D. Vinyl chloride is an example of haloalkene and allyl chloride is an example of haloalkyne.

E. R$-$Cl can be prepared by reacting R$-$OH with $\mathrm{SOCl_2}$ but Ar$-$Cl cannot be prepared by reacting Ar$-$OH with $\mathrm{SOCl_2}$.

Choose the correct answer from the options given below :

An organic compound "$x$" where molar ratio of C, O and H are equal, on treatment with 50% KOH under reflux followed by acidification produced "$y$". The most likely structure of "$y$" is :

[Molar mass of '$x$' is 58 g mol$^{-1}$]

A molecule (X) with following structure under mild acidic condition is hydrolysed to produce (Y) and (Z). Identify the correct statements about (Y) and (Z).

skeletal structure of (X) — an unsymmetrical vinyl ether, $\mathrm{CH_3{-}CH{=}CH{-}O{-}C(CH_3){=}CH_2}$ (prop-1-en-1-yl prop-1-en-2-yl ether)

A. Both (Y) and (Z) have same molar mass.

B. (Y) and (Z) can be distinguished from each other by $\mathrm{NaHCO_3}$.

C. (Y) and (Z) react with HCN with same rates.

D. (Y) and (Z) undergo addition reaction with 2,4-DNP.

Choose the correct answer from the options given below :

Identify compounds A and E in the following reaction sequence.

1-ethyl-4-nitrobenzene (benzene ring with $\mathrm{C_2H_5}$ and $\mathrm{NO_2}$ para to each other)

$\xrightarrow{\mathrm{Br_2/AlBr_3}}$ A $\xrightarrow[\mathrm{HCl}]{\mathrm{Sn}}$ B $\xrightarrow[\text{273-278 K}]{\mathrm{NaNO_2/HCl}}$ C $\xrightarrow{\mathrm{C_2H_5OH}}$ D $\xrightarrow[\text{(ii) } \mathrm{H_3O^+}]{\text{(i) } \mathrm{KMnO_4/KOH}}$ E

Identify the correct pair having amino acid (A) and the hormone (B) that is iodinated derivative of the amino acid (A).

(T and Y represent one letter code for amino acids)

Amino acid (A) $\quad$ Hormone (B)

Among $\mathrm{Fe^{2+}}$, $\mathrm{Fe^{3+}}$, $\mathrm{Cr^{2+}}$ and $\mathrm{Zn^{2+}}$, the ion that shows positive borax bead test and with highest ionisation enthalpy is :

The surface of sodium metal is irradiated with radiation of wavelength $x$ nm. The kinetic energy of ejected electrons is $2.8 \times 10^{-20}$ J. The work function of sodium is 2.3 eV. The value of $x$ is __________ $\times 10^{2}$ nm. (Nearest integer)

(Given : $h = 6.6 \times 10^{-34}$ J s ; 1 eV $= 1.6 \times 10^{-19}$ J; $c = 3.0 \times 10^{8}$ m s$^{-1}$)

Consider the following gas phase reaction being carried out in a closed vessel at 25°C.

$$\mathrm{2A(g) \longrightarrow 4B(g) + C(g)}$$

time (min)	total pressure of the system (mm Hg)
30	300
$\infty$	600

The pressure of C(g) at 30 minutes time interval would be __________ mm Hg. (nearest integer)

Consider the following two half-cell reactions along with the standard reduction potential given :

$$\mathrm{CO_2 + 6H^+ + 6e^- \longrightarrow CH_3OH + H_2O} \qquad E^{o}_{red} = 0.02\ \mathrm{V}$$

$$\mathrm{\tfrac{1}{2}O_2 + 2H^+ + 2e^- \longrightarrow H_2O} \qquad E^{o}_{red} = 1.23\ \mathrm{V}$$

A fuel cell was set up using the above two reactions such that the cell operates under the standard condition of 1 bar pressure and 298 K temperature. The fuel cell works with 80% efficiency. If the work derived from the cell using 1 mol of $\mathrm{CH_3OH}$ is used to compress an ideal gas isothermally against a constant pressure of 1 kPa, then the change in the volume of the gas, $\Delta V =$ __________ m$^3$. (nearest integer)

Given : $F = 96500$ C mol$^{-1}$

Number of paramagnetic ions among the following d- and f-block metal ions is __________.

$\mathrm{Mn^{2+}}$, $\mathrm{Cu^{2+}}$, $\mathrm{Zn^{2+}}$, $\mathrm{Yb^{2+}}$, $\mathrm{Sc^{3+}}$, $\mathrm{La^{3+}}$, $\mathrm{Gd^{3+}}$, $\mathrm{Lu^{3+}}$, $\mathrm{Ti^{4+}}$, $\mathrm{Ce^{4+}}$

(Atomic number of Mn = 25, Cu = 29, Zn = 30, Yb = 70, Sc = 21, La = 57, Gd = 64, Lu = 71, Ti = 22, Ce = 58)

Consider the following reactions sequence

1-methyl-4-nitrobenzene (benzene ring with $\mathrm{NO_2}$ and $\mathrm{H_3C}$ para to each other)

$\xrightarrow[\substack{\text{(ii) } \mathrm{(CH_3CO)_2O} \\ \text{(iii) } \mathrm{Br_2/AlBr_3} \\ \text{(iv) } \mathrm{H_3O^+}}]{\text{(i) } \mathrm{Sn/HCl;\ OH^-}}$ Major Product (P)

When the product (P) is subjected to Carius analysis using $\mathrm{AgNO_3}$, 1.0 g of the product (P) will produce __________ g of the precipitate of AgBr. (Nearest Integer)

(Given : molar mass in g mol$^{-1}$ C : 12, H : 1, O : 16, N : 14, Br : 80, Ag : 108)