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Chemistry

Given below are two statements:
Statement I: The dipole moment of \( \mathrm{R{-}CN} \) is greater than \( \mathrm{R{-}NC} \) and \( \mathrm{R{-}NC} \) can undergo hydrolysis under acidic medium to produce .
Statement II: \( \mathrm{R{-}CN} \) hydrolyses under acidic medium to produce a compound which on treatment with \( \mathrm{SOCl_2} \), followed by the addition of \( \mathrm{NH_3} \) gives another compound (\( x \)). This compound (\( x \)) on treatment with \( \mathrm{NaOCl/NaOH} \) gives a product, that on treatment with \( \mathrm{CHCl_3/KOH/\Delta} \) produces \( \mathrm{R{-}NC} \).
In the light of the above statements, choose the correct answer from the options given below:

52.

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 under optimum pH, it forms a condensation product with acetophenone only.
In the light of the above statements, choose the correct answer from the options given below:

53.

From the following, how many compounds contain at least one secondary alcohol?

Choose the correct answer from the options given below:

54.

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 (\( Y \)).
In the light of the above statements, choose the correct answer from the options given below:

55.

At \( 298 \, \text{K} \), the mole percentage of \( \mathrm{N_2(g)} \) in air is \( 80\% \). Water is in equilibrium with air at a pressure of \( 10 \, \text{atm} \). What is the mole fraction of \( \mathrm{N_2(g)} \) in water at \( 298 \, \text{K} \)? ( \( K_H \) for \( \mathrm{N_2} \) is \( 6.5 \times 10^{7} \, \text{mm Hg} \) )

56.

The wavelength of light absorbed for the following complexes are in the order
\( \left[\mathrm{Co(NH_3)_6}\right]^{3+} ; \left[\mathrm{Co(H_2O)_6}\right]^{3+} ; \left[\mathrm{Co(CN)_6}\right]^{3-} ; \left[\mathrm{Co(NH_3)_5(H_2O)}\right]^{3+} ; \left[\mathrm{CoF_6}\right]^{3-} \)
\( (\mathrm{I}) \quad \) \( (\mathrm{II}) \quad\) \( (\mathrm{III}) \quad\) \( (\mathrm{IV}) \quad\) \((\mathrm{V}) \)

57.

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:

58.

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:

59.

"\( X \)" 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:

60.

In the Group analysis of cations, \( \mathrm{Ba^{2+}} \) and \( \mathrm{Ca^{2+}} \) are precipitated respectively as:

61.

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

62.

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:

63.

Consider the following gaseous equilibrium in a closed container of volume \( 'V' \) at \( T(\text{K}) \).
\( \mathrm{P_2(g) + Q_2(g) \rightleftharpoons 2PQ(g)} \)
\( 2 \) moles each of \( \mathrm{P_2(g)} \), \( \mathrm{Q_2(g)} \) and \( \mathrm{PQ(g)} \) are present at equilibrium. Now one mole each of \( \mathrm'{P_2}' \) and \( \mathrm'{Q_2}' \) are added to the equilibrium keeping the temperature at \( T(\text{K}) \). The number of moles of \( \mathrm{P_2} \), \( \mathrm{Q_2} \) and \( \mathrm{PQ} \) at the new equilibrium, respectively, are:

64.

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

65.

Two liquids \( \mathrm{A} \) and \( \mathrm{B} \) form an ideal solution at temperature \( T \, \text{K} \). At \( T \, \text{K} \), the vapour pressures of pure \( \mathrm{A} \) and \( \mathrm{B} \) are \( 55 \) and \( 15 \, \text{kN m}^{-2} \) respectively. What is the mole fraction of \( \mathrm{A} \) in solution of \( \mathrm{A} \) and \( \mathrm{B} \) in equilibrium with a vapour in which the mole fraction of \( \mathrm{A} \) is \( 0.8 \)?

66.

The correct order of C, N, O and F in terms of second ionisation potential is:

67.

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 effect with electrophile.
(C) Inductive effect is responsible for high melting point, boiling point and dipole moment of polar compounds.
(D) The greater the number of alkyl groups attached to the doubly bonded carbon atoms, higher is the heat of hydrogenation.
(E) Stability of carbanion increases with the increase in s – character of the carbon carrying the negative charge.
Choose the correct answer from the options given below:

68.

Choose the INCORRECT statement.

69.

The heat of atomization of methane and ethane are ‘\( x \)’ \( \mathrm{kJ\,mol^{-1}} \) and ‘\( y \)’ \( \mathrm{kJ\,mol^{-1}} \) respectively. The longest wavelength (\( \lambda \)) of light capable of breaking the C–C bond can be expressed in SI unit as:

70.

One mole of \( \mathrm{Cl_2(g)} \) was passed into \( 2 \, \mathrm{L} \) of cold \( 2 \, \mathrm{M} \) \( \mathrm{KOH} \) solution. After the reaction, the concentrations of \( \mathrm{Cl^-} \), \( \mathrm{ClO^-} \) and \( \mathrm{OH^-} \) are respectively (assume volume remains constant)

71.

Molar conductivity of a weak acid \( \mathrm{HQ} \) of concentration \( 0.18 \, \mathrm{M} \) was found to be \( \dfrac{1}{30} \) of the molar conductivity of another weak acid \( \mathrm{HZ} \) with concentration of \( 0.02 \, \mathrm{M} \). If \( \lambda^{\circ}_{Q^-} \) happened to be equal with \( \lambda^{\circ}_{Z^-} \), then the difference of the \( \mathrm{p}K_a \) values of the two weak acids \( (\mathrm{p}K_a{(\mathrm{HQ})} - \mathrm{p}K_a{(\mathrm{HZ})}) \) is ______. (Nearest integer)
[Given: degree of dissociation (\( \alpha \)) \( \ll 1 \) for both weak acids, \( \lambda^{\circ} \) : limiting molar conductivity of ions]

72.

Grignard reagent \( \mathrm{RMgBr} \) (\( P \)) reacts with water and forms a gas (\( Q \)). One gram of \( Q \) occupies \( 1.4 \, \mathrm{dm^3} \) at STP. \( Q \) on reaction with dry ice in dry ether followed by \( \mathrm{H_3O^+} \) forms a compound (\( Z \)). \( 0.1 \) mole of (\( Z \)) will weigh ______ \( \mathrm{g} \). (Nearest integer)

73.

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

74.

A chromium complex with a formula \( \mathrm{CrCl_3\cdot 6H_2O} \) has a spin only magnetic moment value of \( 3.87 \, \text{BM} \) and its solution conductivity corresponds to \( 1:2 \) electrolyte. \( 2.75 \, \text{g} \) of the complex solution was initially passed through a cation exchanger. The solution obtained after the process was reacted with excess of \( \mathrm{AgNO_3} \). The amount of \( \mathrm{AgCl} \) formed in the above process is __________ \( \text{g} \). (Nearest integer)
[Given: Molar mass in \( \text{g mol}^{-1} \) Cr : \( 52 \); Cl : \( 35.5, \) Ag: \( 108 \), O: \( 16 \), H: \( 1 \)]

75.

\( 0.25 \, \text{g} \) of an organic compound “A” containing carbon, hydrogen and oxygen was analyzed 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 be \( 0.15 \, \text{g} \) and \( 0.1837 \, \text{g} \), respectively. The percentage of oxygen in compound A is ______ \( \% \). (Nearest integer)
(Given: molar mass in \( \text{g mol}^{-1} \) H : \( 1 \), C : \( 12 \), O : \( 16 \))

JEE Main 2026 24th Jan Evening Shift

Mathematics Physics Chemistry

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\( 0.25 \, \text{g} \) of an organic compound “A” containing carbon, hydrogen and oxygen was analyzed 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 be \( 0.15 \, \text{g} \) and \( 0.1837 \, \text{g} \), respectively. The percentage of oxygen in compound A is ______ \( \% \). (Nearest integer)
(Given: molar mass in \( \text{g mol}^{-1} \) H : \( 1 \), C : \( 12 \), O : \( 16 \))

JEE MainsJEE AdvanceBITSATJEE Mains | PYQ

JEE Mains JEE Advance BITSAT
JEE Mains | PYQ