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Chemistry

The ratio of mass percentage \( (\text{w/w}) \) of \( \mathrm{C:H} \) in a hydrocarbon is \( 12:1 \). It has two carbon atoms. The weight \( (\text{in g}) \) of \( \mathrm{CO_{2}(g)} \) formed when \( 3.38\ \text{g} \) of this hydrocarbon is completely burnt in oxygen is:

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

52.

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 \( 0.1 \, \mathrm{M} \) HCl solution. The concentration of \( \mathrm{HA^-} \) in the resultant solution is:

53.

\( \mathrm{SF_4} \) is isostructural with:

A. \( \mathrm{BrF_4^-} \) B. \( \mathrm{CH_4} \) C. \( \mathrm{IF_4^+} \) D. \( \mathrm{XeF_4} \) E. \( \mathrm{XeO_2F_2} \)

Choose the correct answer from the options given below:

54.

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

55.

Solution A is prepared by dissolving \( 1 \, \mathrm{g} \) of a protein (molar mass \( = 50000 \, \mathrm{g \, mol^{-1}} \)) in \( 0.5 \, \mathrm{L} \) of water at \( 300 \, \mathrm{K} \). Its osmotic pressure is \( x \) bar. Solution B is made by dissolving \( 2 \, \mathrm{g} \) of same protein in \( 1 \, \mathrm{L} \) of water at \( 300 \, \mathrm{K} \). 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: \( (R = 0.083 \, \mathrm{L \, bar \, mol^{-1} \, K^{-1}}) \)

56.

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

Given : \( K_a = 5 \times 10^{-4} \)
\( \mathrm{p}K_a = 3.3 \)
\( \alpha \ll 1 \)

57.

Consider the reaction \( a\mathrm{X} \rightarrow b\mathrm{Y} \), for which the rate constant at \( 30^\circ \text{C} \) is \( 1 \times 10^{-3} \, \text{mol}^{-1} \, \text{L} \, \text{s}^{-1} \). Which of the following statements are true?

A. When concentration of ‘\( \mathrm{X} \)’ 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 \( \mathrm{X} \).

D. Decomposition of \( \mathrm{N}_2\mathrm{O}_5 \) is an example of the above reaction.

E. is valid for the above reaction versus time.

Choose the correct answer from the options given below:

58.

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

59.

Given below are two statements:
Statement I: The second ionization enthalpy of \( \mathrm{B}, \mathrm{Al} \) and \( \mathrm{Ga} \) is in the order of \( \mathrm{B} > \mathrm{Al} > \mathrm{Ga} \).
Statement II: The correct order in terms of first ionization enthalpy is \( \mathrm{Si} < \mathrm{Ge} < \mathrm{Pb} < \mathrm{Sn} \).
In the light of the above statements, choose the correct answer from the options given below:

60.

Given below are two statements:
Statement I: Among \( \mathrm{Zn}, \mathrm{Mn}, \mathrm{Sc} \) and \( \mathrm{Cu} \), the energy required to remove the third valence electron is highest for \( \mathrm{Zn} \) and lowest for \( \mathrm{Sc} \).
Statement II: The correct order of the following complexes in terms of CFSE is \( [\mathrm{Co}(\mathrm{H_2O})_6]^{2+} < [\mathrm{Co}(\mathrm{H_2O})_6]^{3+} < [\mathrm{Co}(\mathrm{en})_3]^{3+} \).
In the light of the above statements, choose the correct answer from the options given below:

61.

Which of the following complexes will show coordination isomerism?

A. \( [\mathrm{Ag}(\mathrm{NH}_3)_2][\mathrm{Ag}(\mathrm{CN})_2] \)

B. \( [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Cr}(\mathrm{CN})_6] \)

C. \( [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Co}(\mathrm{CN})_6] \)

D. \( [\mathrm{Fe}(\mathrm{NH}_3)_6][\mathrm{Co}(\mathrm{CN})_6] \)

E. \( [\mathrm{Co}(\mathrm{NH}_3)_6][\mathrm{Fe}(\mathrm{CN})_6] \)

Choose the correct answer from the options given below:

62.

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 \( \mathrm{C} \), \( \mathrm{H} \) and \( \mathrm{O} \) are \( 12 \), \( 1 \) and \( 16 \) g \( \mathrm{mol}^{-1} \) respectively.)

63.

Given below are two statements:

Statement I: In , the carbocation is stabilized by \( +R \) effect of \( -\mathrm{OCH}_3 \) group.

Statement II: In , the carbanion is stabilized by \( -R \) effect of \( -\mathrm{NO}_2 \) group.

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

64.

The compound \( (\mathrm{X}) \) on

\((i)\) on heating in the presence of anhydrous \( \mathrm{AlCl}_3 \) and \( \mathrm{HCl} \) gas gives \( 2, 4 \)-dimethyl pentane

\((ii)\) aromatization gives toluene and

\((iii)\) cyclisation gives methyl cyclohexane

The correct name of compound \( (\mathrm{X}) \) is:

65.

Correct statements regarding alkyl halides \( (\mathrm{R}-\mathrm{X}) \) among the following are:

A. Alcohol being less polar solvent as compared to water, alcoholic \( \mathrm{KOH} \) favours elimination reaction with \( \mathrm{R}-\mathrm{X} \).

B. Order of reactivity towards \( \mathrm{S_{N}1} \) mechanism is \( \mathrm{C_6H_5-CH_2-Cl} > \mathrm{C_6H_5-CHCl-C_6H_5} \).

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

Choose the correct answer from the options given below:

66.

An organic compound “\( x \)” where molar ratio of \( \mathrm{C} \), \( \mathrm{O} \) and \( \mathrm{H} \) are equal, on treatment with \( 50\% \) \( \mathrm{KOH} \) under reflux followed by acidification produced “\( y \)”. The most likely structure of “\( y \)” is:

[Molar mass of “\( x \)” is \( 58 \) g \( \mathrm{mol}^{-1} \)]

67.

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

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 \( \mathrm{HCN} \) with same rates.

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

Choose the correct answer from the options given below:

68.

Identify compounds A and E in the following reaction sequence.

69.

Identify the correct pair having amino acid \( (A) \) and the hormone \( (B) \) that is iodinated derivative of the amino acid \( (A) \).
\( (T \text{ and } Y \text{ represent one letter code for amino acids}) \)

70.

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 ionization enthalpy is:

71.

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

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

72.

Consider the following phase reaction being carried out in a closed vessel at \( 25^\circ \text{C} \).
\( 2A(g) \rightarrow 4B(g) + C(g) \)

The pressure of \( C(g) \) at \( 30 \) minutes time interval would be ________ \( \text{mm Hg} \). (nearest integer)

73.

Consider the following two half-cell reactions along with the standard reduction potential given:
\( \text{CO}_{2} + 6\text{H}^{+} + 6e^{-} \rightarrow \text{CH}_{3}\text{OH} + \text{H}_{2}\text{O} \quad E^{0}_{\text{red}} = 0.02 \, \text{V} \)
\( \dfrac{1}{2}\text{O}_{2} + 2\text{H}^{+} + 2e^{-} \rightarrow \text{H}_{2}\text{O} \quad E^{0}_{\text{red}} = 1.23 \, \text{V} \)
A fuel cell was set up using the above two reactions such that the cell operates under the standard condition of \( 1 \, \text{bar} \) pressure and \( 298 \, \text{K} \) temperature. The fuel cell works with \( 80\% \) efficiency. If the work derived from the cell using \( 1 \, \text{mol} \) of \( \text{CH}_{3}\text{OH} \) is used to compress an ideal gas isothermally against a constant pressure of \( 1 \, \text{kPa} \), then the change in the volume of the gas, \( \Delta V = \) _________ \( \text{m}^{3} \). (nearest integer)
Given : \( F = 96500 \, \text{C mol}^{-1} \)

74.

Number of paramagnetic ions among the following d- and f-block metal ions is ________.
\( \text{Mn}^{2+}, \text{Cu}^{2+}, \text{Zn}^{2+}, \text{Yb}^{2+}, \text{Sc}^{3+}, \text{La}^{3+}, \text{Gd}^{3+}, \text{Lu}^{3+}, \text{Ti}^{4+}, \text{Ce}^{4+} \).
(Atomic number of Mn \( = 25 \), Cu \( = 29 \), Zn \( = 30 \), Yb \( = 70 \), Sc \( = 21 \), La \( = 57 \), Gd \( = 64 \), Lu \( = 71 \), Ti \( = 22 \), Ce \( = 58 \))

75.

Consider the following reactions sequence

When the product (P) is subjected to Carius analysis using \( \text{AgNO}_{3} \), \( 1.0 \, \text{g} \) of the product (P) will produce ________ \( \text{g} \) of the precipitate of \( \text{AgBr} \). (Nearest Integer)
(Given : molar mass in \( \text{g mol}^{-1} \) C : \( 12 \); H : \( 1 \); O : \( 16 \); N : \( 14 \); Br : \( 80 \); Ag : \( 108 \))

JEE Main 2026 2nd April Evening Shift

Mathematics Physics Chemistry

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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 \( 0.1 \, \mathrm{M} \) HCl solution. The concentration of \( \mathrm{HA^-} \) in the resultant solution is:

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JEE Mains JEE Advance BITSAT
JEE Mains | PYQ