JEE Main 2023 Chemistry Question Paper Jan 31 Shift 2- Download Paper with Solution PDF Here

JEE Main 2023 Chemistry Questions with Solutions

SECTION A

Question 1:

In the following halogenated organic compounds, the one with the maximum number of chlorine atoms in its structure is:

• (1) Chloral
• (2) Gammaxene
• (3) Chloropicrin
• (4) Freon-12

Incorrect statement for the use of indicators in acid-base titration:

• (1) Methyl orange may be used for a weak acid vs weak base titration.
• (2) Methyl orange is a suitable indicator for a strong acid vs weak base titration.
• (3) Phenolphthalein is a suitable indicator for a weak acid vs strong base titration.
• (4) Phenolphthalein may be used for a strong acid vs strong base titration.

Which of the following compounds are not used as disinfectants?
(A) Chloroxylenol

(B) Bithional

(C) Veronal

(D) Prontosil

(E) Terpineol

Choose the correct answer from the options given below:

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

A hydrocarbon ‘X’ with formula \( C_6H_8 \) uses two moles of \( H_2 \) on catalytic hydrogenation of its one mole. On ozonolysis, ‘X’ yields two moles of methane dicarbaldehyde. The hydrocarbon ‘X’ is:

• (1) hexa-1, 3, 5-triene
• (2) 1-methylcyclopenta-1, 4-diene
• (3) cyclohexa-1, 3-diene
• (4) cyclohexa-1, 4-diene

Cyclohexylamine when treated with nitrous acid yields (P). On treating (P) with PCC results in (Q). When (Q) is heated with dilute NaOH, we get (R). The final product (R) is:

Given below are two statements:
Statement I: Upon heating a borax bead dipped in cupric sulphate in a luminous flame, the colour of the bead becomes green.
Statement II: The green colour observed is due to the formation of copper(I) metaborate.

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

• (1) Both Statement I and Statement II are true
• (2) Statement I is true but Statement II is false
• (3) Both Statement I and Statement II are false
• (4) Statement I is false but Statement II is true

Evaluate the following statements for their correctness:

(A) The elevation in boiling point temperature of water will be same for 0.1 M NaCl and 0.1 M urea.

(B) Azeotropic mixtures boil without change in their composition.

(C) Osmosis always takes place from hypotonic to hypertonic solution.

(D) The density of 32% \( H_2SO_4 \) solution having molarity 4.09 M is approximately 1.26 g mL\(^{-1}\).

(E) A negatively charged sol is obtained when KI solution is added to silver nitrate solution.

Choose the correct answer from the options given below:

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

Compound A, \( C_5H_{10}O_5 \), given a tetraacetate with \( Ac_2O \) and oxidation of A with \( Br_2 - H_2O \) gives an acid, \( C_5H_{10}O_6 \). Reduction of A with HI gives isopentane. The possible structure of A is:

Arrange the following orbitals in decreasing order of energy?
(A) \( n = 3, l = 0, m = 0 \)

(B) \( n = 4, l = 1, m = 0 \)

(C) \( n = 3, l = 1, m = 0 \)

(D) \( n = 3, l = 2, m = 1 \)

The correct option for the order is:

• (1) B \(>\) D \(>\) C \(>\) A
• (2) D \(>\) B \(>\) C \(>\) A
• (3) A \(>\) C \(>\) B \(>\) D
• (4) D \(>\) B \(>\) A \(>\) C

The Lewis acid character of boron tri halides follows the order:

• (1) \( BCl_3 > BBr_3 > BCl_3 > BF_3 \)
• (2) \( BCl_3 > BF_3 > BBr_3 > B1_3 \)
• (3) \( BF_3 > BCl_3 > BBr_3 > B1_3 \)
• (4) \( B1_3 > BBr_3 > BCl_3 > BF_3 \)

Match List-I with List-II:


\begin{tabular{|l|l|
\hline
List-I & List-II

\hline
(A) Physiosorption & I. Single layer adsorption

\hline
(B) Chemisorption & II. 20-40 kJ mol\(^{-1}\)

\hline
(C) \( N_2(g) + 3H_2(g) \xrightarrow{Fe} 2NH_3(g) \) & III. Chromatography

\hline
(D) Analytical Application or Adsorption & IV. Heterogeneous catalysis

\hline
\end{tabular



Choose the correct answer from the options given below:

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

Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R)

Assertion (A): The first ionization enthalpy of 3d series elements is more than that of group 2 metals.

Reason (R): In 3d series of elements, successive filling of d-orbitals takes place.

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

• (1) Both (A) and (R) are true and (R) is the correct explanation of (A)
• (2) Both (A) and (R) are true but (R) is not the correct explanation of (A)
• (3) (A) is false but (R) is true
• (4) (A) is true but (R) is false

The element playing a significant role in neuromuscular function and interneuronal transmission is:

• (1) Be
• (2) Ca
• (3) Li
• (4) Mg

Given below are two statements:
Statement I: \( H_2O_2 \) is used in the synthesis of Cephalosporin.
Statement II: \( H_2O_2 \) is used for the restoration of aerobic conditions to sewage wastes.

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

• (1) Both Statement I and Statement II are correct
• (2) Statement I is incorrect but Statement II is correct
• (3) Statement I is correct but Statement II is incorrect
• (4) Both Statement I and Statement II are incorrect

The normal rain water is slightly acidic and its pH value is 5.6 because of which one of the following?

• (1) \( CO_2 + H_2O \rightarrow H_2CO_3 \)
• (2) \( 4NO_2 + 2H_2O \rightarrow 4HNO_3 \)
• (3) \( SO_2 + O_2 + 2H_2O \rightarrow H_2SO_4 \)
• (4) \( 2N_2O_5 + H_2O \rightarrow 2HNO_3 \)

When a hydrocarbon A undergoes complete combustion it requires 11 equivalents of oxygen and produces 4 equivalents of water. What is the molecular formula of A?

• (1) \( C_9H_8 \)
• (2) \( C_{11}H_4 \)
• (3) \( C_5H_8 \)
• (4) \( C_{11}H_8 \)

An organic compound [A] (\( C_4H_11N \)) shows optical activity and gives \( N_2 \) gas on treatment with \( HNO_2 \). The compound [A] reacts with \( PhSO_2Cl \) producing a compound which is soluble in KOH. The structure of A is:

Which one of the following statements is incorrect?

• (1) Boron and Indium can be purified by zone refining method.
• (2) Van Arkel method is used to purify tungsten.
• (3) Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast.
• (4) The malleable iron is prepared from cast iron by oxidizing impurities in a reverberatory furnace.

Which of the following elements have half-filled f-orbitals in their ground state?
(Given: atomic number
Sm = 62; Eu = 63; Tb = 65; Gd = 64; Pm = 61)
(A) Sm

(B) Eu

(C) Tb

(D) Gd

(E) Pm


Choose the correct answer from the options given below:

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

In Dumas method for the estimation of \( N_2 \), the sample is heated with copper oxide and the gas evolved is passed over:

• (1) Ni
• (2) Copper gauze
• (3) Pd
• (4) Copper oxide

SECTION B

Question 21:

If the CFSE of \( [ Ti^{3+} (H_2O)_6 ]^{3+} \) is -96.0 kJ/mol, this complex will absorb maximum at wavelength __ nm. (nearest integer)

Assume Planck's constant \( h = 6.4 \times 10^{-34} \, J s \), speed of light \( c = 3.0 \times 10^8 \, m/s \), and Avogadro's constant \( N_A = 6 \times 10^{23} \, mol^{-1} \).

Amongst the following, the number of species having the linear shape is: \[ XeF_2, I_3^-, C_3O_2, I_5^-, CO_2, SO_2, BeCl_2 \quad and \quad BCI_2^+ \]

The resistivity of a 0.8 M solution of an electrolyte is \( 5 \times 10^{-3} \, \Omega \, cm \). Its molar conductivity is \( \_\_ \times 10^4 \, \Omega^{-1} \, cm^2 \, mol^{-1} \) (Nearest integer).

At 298 K, the solubility of silver chloride in water is \( 1.434 \times 10^{-3} \, g L^{-1} \). The value of \( -\log K_{sp} \) for silver chloride is:

(Given mass of Ag is 107.9 g mol\(^{-1}\) and mass of Cl is 35.5 g mol\(^{-1}\))

A sample of a metal oxide has formula \( M_0.83O_1.00 \).

The metal M can exist in two oxidation states \( +2 \) and \( +3 \). In the sample of \( M_0.83O_1.00 \), the percentage of metal ions existing in the \( +2 \) oxidation state is __ % (nearest integer).

Assume carbon burns according to the following equation: \[ 2C(s) + O_2(g) \rightarrow 2CO(g) \]
When 12 g of carbon is burnt in 48 g of oxygen, the volume of carbon monoxide produced is \( \_ \times 10^{-1} \) L at STP (nearest integer).

Given: Assume CO as ideal gas, Mass of C is 12 g mol\(^{-1}\), Mass of O is 16 g mol\(^{-1}\), and molar volume of an ideal gas at STP is 22.7 L mol\(^{-1}\).

The number of alkali metal(s), from Li, K, Cs, Rb having ionization enthalpy greater than 400 kJ mol\(^{-1}\) and forming stable super oxides is __

Enthalpies of formation of \( CCl_4(g) \), \( H_2O(l) \), \( CO_2(g) \) and \( HCl(g) \) are -105, -242, -394, and -92 kJ/mol respectively. The magnitude of enthalpy of the reaction given below is __ kJ/mol (nearest integer): \[ CCl_4(g) + 2H_2O(l) \rightarrow CO_2(g) + 4HCl(g) \]

The number of molecules which gives halform test among the following molecules is:

The rate constant for a first order reaction is 20 min\(^{-1}\). The time required for the initial concentration of the reactant to reduce to its \( \frac{1}{32} \) level is __ \( \times 10^{-2} \) min. (Nearest integer)
(Given: \( \ln 10 = 2.303 \), \( \log 2 = 0.3010 \))