JEE Main 2023 Chemistry Question Paper Jan 31 Shift 1- Download Paper with Solution PDF Here

JEE Main 2023 Chemistry Questions with Solutions

SECTION A

Question 1:

Nd\(^{2+}\) = ..........

• (1) \( 4f^2 6s^2 \)
• (2) \( 4f^4 \)
• (3) \( 4f^3 \)
• (4) \( 4f^4 6s^2 \)

The methods NOT involved in concentration of ore are

(A) Liquation

(B) Leaching

(C) Electrolysis

(D) Hydraulic washing

(E) Froth flotation


Choose the correct answer from the options given below:

• (1) B, D and C only
• (2) C, D and E only
• (3) A and C only
• (4) B, D and E only

Consider the following reaction \[ Propanal + Methanal \xrightarrow{(i) dil. NaOH} \xrightarrow{(ii) A} \xrightarrow{(iii) NaCN} \xrightarrow{(iv) H_2O} Product B \, (C_5H_8O_3) \]

The correct statement for product B is:

• (1) Optically active and adds one mole of bromine
• (2) Racemic mixture and is neutral
• (3) Racemic mixture and gives a gas with saturated NaHCO₃ solution
• (4) Optically active alcohol and is neutral

The correct order of basicity of oxides of vanadium is:

• (1) \( V_2O_3 > V_2O_4 > V_2O_5 \)
• (2) \( V_2O_3 > V_2O_5 > V_2O_4 \)
• (3) \( V_2O_5 > V_2O_3 > V_2O_4 \)
• (4) \( V_2O_4 > V_2O_3 > V_2O_5 \)

When \( Cu^{2+} \) ion is treated with KI, a white precipitate, X appears in solution. The solution is titrated with sodium thiosulphate, the compound Y is formed. X and Y respectively are:

• (1) \( X = CuI_2, \, Y = Na_2S_4O_5 \)
• (2) \( X = CuI_2, \, Y = Na_2S_4O_6 \)
• (3) \( X = CuI, \, Y = Na_2S_4O_3 \)
• (4) \( X = CuI, \, Y = Na_2S_4O_6 \)

The reaction sequence is:

• (1)
• (2)
• (3)
• (4)

Correct Answer: (4)
View Solution

Cobalt chloride when dissolved in water forms pink colored complex X which has octahedral geometry. This solution on treating with cone HCl forms deep blue complex Y which has a Z geometry. X, Y and Z, respectively, are:

• (1) \( X = [Co(H_2O)_6]^{2+}, \, Y = [CoCl_4]^{2-}, \, Z = Tetrahedral \)
• (2) \( X = [Co(H_2O)_6]^{3+}, \, Y = [CoCl_3]^{3-}, \, Z = Octahedral \)
• (3) \( X = [Co(H_2O)_6]^{3+}, \, Y = [CoCl_4]^{2-}, \, Z = Octahedral \)
• (4) \( X = [Co(H_2O)_6]^{2+}, \, Y = [CoCl_4]^{2-}, \, Z = Tetrahedral \)

Identify X, Y, and Z in the following reaction. (Equation not balanced) \[ ClO + NO_2 \rightarrow X \xrightarrow{H_2O} Y + Z \]

• (1) \( X = ClONO_2, \, Y = HOCl, \, Z = NO_2 \)
• (2) \( X = ClONO_2, \, Y = HCl, \, Z = HNO_3 \)
• (3) \( X = ClONO_2, \, Y = HOCl, \, Z = HNO_3 \)
• (4) \( X = ClO_3, \, Y = Cl_2, \, Z = NO_2 \)

The correct order of melting point of dichlorobenzenes is:

• (1)
• (2)
• (3)
• (4)

Correct Answer: (4)
View Solution

A protein 'X' with molecular weight of 70,000 u, on hydrolysis gives amino acids. One of these amino acids is

• (1)
• (2)
• (3)
• (4)

Correct Answer: (2)
View Solution

Which transition in the hydrogen spectrum would have the same wavelength as the Balmer type transition from \( n = 4 \) to \( n = 2 \) of He\(^{+}\) spectrum?

• (1) \( n = 2 \, to \, 1 \)
• (2) \( n = 1 \, to \, 3 \)
• (3) \( n = 1 \, to \, 2 \)
• (4) \( n = 3 \, to \, 4 \)

Match items of column I and II

Column I (Mixture of compounds)                            Column II (Separation Technique)
A. H₂O/CH₃Cl                                                                            i. Crystallization
B.                                                            ii. Differential solvent extraction
C. Kerosene/Naphthalene                                                        iii. Column chromatography

D. C₆H₅O/NaCl                                                                            iv. Fractional Distillation

Correct match is:

• (1) A-(iii), B-(iv), C-(ii), D-(i)
• (2) A-(ii), B-(iii), C-(ii), D-(iv)
• (3) A-(ii), B-(iii), C-(iv), D-(i)
• (4) A-(ii), B-(iv), C-(i), D-(iii)

The correct increasing order of the ionic radii is:

• (1) \( Cl^- < Ca^{2+} < K^+ < S^{2-} \)
• (2) \( K^+ < S^{2-} < Ca^{2+} < Cl^- \)
• (3) \( S^{2-} < Cl^- < Ca^{2+} < K^+ \)
• (4) \( Ca^{2+} < K^+ < Cl^- < S^{2-} \)

H\(_2\)O\(_2\) acts as a reducing agent in:

• (1) \( 2NaOCl + H_2O_2 \rightarrow 2NaCl + H_2O + O_2 \)
• (2) \( 2Fe^{2+} + 2H_2O_2 \rightarrow 2Fe^{3+} + 2H_2O \)
• (3) \( Mn^{2+} + 2H_2O_2 \rightarrow MnO_2 + 2H_2O \)
• (4) \( Na_2S_4O_6 + 4H_2O_2 \rightarrow Na_2SO_4 + 4H_2O \)

Which of the following artificial sweeteners has the highest sweetness value in comparison to cane sugar?

• (1) Aspartame
• (2) Sucralose
• (3) Alitame
• (4) Saccharin

Match List I with List II

List I                                                                      List II
A. \(XeF_4\)                                                         I. See-saw
B. \(SF_4\)                                                           II. Square planar
C. \(NH_4^+\)                                                      III. Bent T-shaped
D. \(BrF_3\)                                                          IV. Tetrahedral

Choose the correct answer from the options given below:

• (1) A-IV, B-III, C-II, D-I
• (2) A-II, B-III, C-III, D-IV
• (3) A-I, B-I, C-II, D-III
• (4) A-I, B-I, C-IV, D-III

Choose the correct set of reagents for the following conversion \[ trans (Ph-CH=CH-CH_3) \rightarrow cis (Ph-CH=CH-CH_3) \]

• (1) \( Br_2, \, alc. KOH, \, NaNH_2, \, Na(Liq NH_3) \)
• (2) \( Br_2, \, aq KOH, \, NaNH_2, \, H_2 \, Lindlar Catalyst \)
• (3) \( Br_2, \, aq KOH, \, NaNH_2, \, Na(Liq NH_3) \)
• (4) \( Br_2, \, alc. KOH, \, NaNH_2, \, Lindlar Catalyst \)

Adding surfactants in non-polar solvent, the micelles structure will look like (Surfactant structure):

• (1) b
• (2) c
• (3) a
• (4) d

An organic compound 'A' with empirical formula \(C_6H_6\)O gives sooty flame on burning. Its reaction with bromine solution in low polarity solvent results in high yield of B. B is:

• (1)
• (2)
• (3)
• (4)

Correct Answer: (1)
View Solution

Which one of the following statements is correct for electrolysis of brine solution?

• (1) \( Cl_2 \) is formed at cathode
• (2) \( O_2 \) is formed at cathode
• (3) \( H_2 \) is formed at anode
• (4) \( OH^- \) is formed at cathode

SECTION B

Question 21:

The logarithm of equilibrium constant for the reaction \[ Pd^{2+} (aq) + 4Cl^- (aq) \rightleftharpoons PdCl_4^{2-} (aq) \]
is:

Given: \[ 2.303RT = 0.06\, V, \quad F = 96,485\, C/mol, \quad E^\circ = 0.83\, V, \quad E^\circ = 0.65\, V \]

\[ \textbf{A} \rightarrow \textbf{B} \]

The rate constants of the above reaction at 200 K and 300 K are 0.03 min\(^{-1}\) and 0.05 min\(^{-1}\) respectively.

The activation energy for the reaction is \hspace{2cm} J (Nearest integer)

Given: \[ \text{ln} \, 10 = 2.3, \quad R = 8.3 \, \text{J K}^{-1} \text{mol}^{-1}, \quad \log 5 = 0.70, \quad \log 3 = 0.48, \quad \log 2 = 0.30 \]

The enthalpy change for the conversion of \[ \frac{1}{2} Cl_2(g) \rightarrow Cl^-(aq) \, is \, (-) \, ...... kJ mol^{-1} \, (Nearest integer) \]

Given: \[ \Delta_{f}H^\circ(Cl_2(g)) = 240 \, kJ mol^{-1}, \quad \Delta_{g}H^\circ(Cl_2(g)) = -350 \, kJ mol^{-1}, \quad \Delta_{hyd}H^\circ(Cl^-) = -380 \, kJ mol^{-1} \]

On complete combustion, 0.492 g of an organic compound gave 0.792 g of \(CO_2\). The % of carbon in the organic compound is \underline{\hspace{2cm}} (Nearest integer).

Given: \[ \text{Weight of carbon in 0.792 g CO}_2 \]

At 27°C, a solution containing 2.5 g of solute in 250.0 mL of solution exerts an osmotic pressure of 400 Pa. The molar mass of the solute is \hspace{2cm} g mol\(^{-1}\) (Nearest integer).

Given: \[ R = 0.083 \, \text{L bar K}^{-1} \text{mol}^{-1}, \quad \pi = \text{osmotic pressure}, \quad T = 300 \, \text{K}, \quad \text{osmotic pressure} = 400 \, \text{Pa}, \quad 1 \, \text{bar} = 10^5 \, \text{Pa} \]

Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at STP from the reaction of 11.5 g of zinc with excess HCl is \hspace{2cm} L (Nearest integer).

Given: \[ \text{Molar mass of Zn} = 65.4 \, \text{g mol}^{-1}, \quad \text{Molar volume of H}_2 \, \text{at STP} = 22.7 \, \text{L/mol} \]

How many of the transformations given below would result in aromatic amines?

For reaction: \[ \text{SO}_2(g) + \frac{1}{2} \text{O}_2(g) \rightleftharpoons \text{SO}_3(g) \] \( K_p = 2 \times 10^{12} \) at 27°C and 1 atm pressure. The \( K_c \) for the same reaction is \hspace{2cm} (Nearest integer).

Given: \[ R = 0.082 \, \text{L atm K}^{-1} \text{mol}^{-1} \]

The oxidation state of phosphorus in hypophosphoric acid is ________________.

The total pressure of a mixture of non-reacting gases X (0.6 g) and Y (0.45 g) in a vessel is 740 mm of Hg. The partial pressure of the gas X is \hspace{2cm} mm of Hg (Nearest Integer).

Given: \[ \textbf{Molar mass of X} = 20 \, \textbf{g mol}^{-1}, \quad \textbf{Molar mass of Y} = 45 \, \textbf{g mol}^{-1} \]