JEE MAIN - Chemistry (2025 - 28th January Evening Shift)

1

The product B formed in the following reaction sequence is:

JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Hydrocarbons Question 9 English
Answer
(D)
JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Hydrocarbons Question 9 English Option 4
2

The major product of the following reaction is:

JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Hydrocarbons Question 8 English
Answer
(C)
2-Phenylhepta-2,4-diene
3

Given below are two statements:

Statement I:JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Basics of Organic Chemistry Question 9 English 1 and JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Basics of Organic Chemistry Question 9 English 2 are isomeric compounds.

Statement II: JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Basics of Organic Chemistry Question 9 English 3 and JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Basics of Organic Chemistry Question 9 English 4 are functional group isomers.

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

Answer
(B)
Both Statement I and Statement II are true
4
Match List - I with List - II.
List - I (Complex) List - II (Hybridisation of central metal ion)
(A) [CoF6]3- (I) d2sp3
(B) [NiCl4]2- (II) sp3
(C) [Co(NH3)6]3+ (III) sp3d2
(D) [Ni(CN)4]2- (IV) dsp2
Choose the correct answer from the options given below:
Answer
(D)
(A)-(III), (B)-(II), (C)-(I), (D)-(IV)
5

Arrange the following in increasing order of solubility product :

$\mathrm{Ca}(\mathrm{OH})_2, \mathrm{AgBr}, \mathrm{PbS}, \mathrm{HgS}$

Answer
(C)
$\mathrm{HgS}<\mathrm{PbS}<\mathrm{AgBr}<\mathrm{Ca}(\mathrm{OH})_2$
6

Match List-I with List-II.

List - I (Saccharides) List - II (Glycosidic-linkages found)
(A) Sucrose (I) α 1 $-$ 4
(B) Maltose (II) α 1 $-$ 4 and α 1 $-$ 6
(C) Lactose (III) α 1 $-$ β 2
(D) Amylopectin (IV) β 1 $-$ 4

Choose the correct answer from the options given below :

Answer
(A)
(A)-(III), (B)-(I), (C)-(IV), (D)-(II)
7
JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Thermodynamics Question 14 English

An ideal gas undergoes a cyclic transformation starting from the point A and coming back to the same point by tracing the path A→B→C→D→A as shown in the three cases above.

Choose the correct option regarding ΔU :

Answer
(C)
$\Delta \mathrm{U}($ Case-I $)=\Delta \mathrm{U}($ Case-II $)=\Delta \mathrm{U}($ Case-III $)$
8

Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom?

(A) 1s < 2p < 3d < 4s

(B) 1s < 2s = 2p < 3s = 3p

(C) 1s < 2s < 2p < 3s < 3p

(D) 1s < 2s < 4s < 3d

Choose the correct answer from the options given below :

Answer
(D)
(C) and (D) only
9
The amphoteric oxide among $\mathrm{V}_2 \mathrm{O}_3, \mathrm{~V}_2 \mathrm{O}_4$ and $\mathrm{V}_2 \mathrm{O}_5$, upon reaction with alkali leads to formation of an oxide anion. The oxidation state of V in the oxide anion is :
Answer
(B)
+ 5
10

Identify product [A], [B] and [C] in the following reaction sequence.

$\mathrm{CH}_3-\mathrm{C} \equiv \mathrm{CH} \xrightarrow[\mathrm{H}_2]{\mathrm{Pd} / \mathrm{C}}[\mathrm{A}] \xrightarrow[\text { (ii) } \mathrm{Zn}, \mathrm{H}_2 \mathrm{O}]{\text { (i) } \mathrm{O}_3}[\mathrm{~B}]+[\mathrm{C}]$

Answer
(B)
[A]: CH3—CH=CH2, [B]: CH3CHO, [C]: HCHO
11

Identify correct conversion during acidic hydrolysis from the following :

(A) starch gives galactose.

(B) cane sugar gives equal amount of glucose and fructose.

(C) milk sugar gives glucose and galactose.

(D) amylopectin gives glucose and fructose.

(E) amylose gives only glucose.

Choose the correct answer from the options given below :

Answer
(C)
(B), (C) and (E) only
12

The total number of compounds from below when treated with hot KMnO4, giving benzoic acid is:

JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 11 English 1JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 11 English 2
Answer
(C)
5
13
Assume a living cell with 0.9% (w/w) of glucose solution (aqueous). This cell is immersed in another solution having equal mole fraction of glucose and water.
(Consider the data upto first decimal place only)

The cell will :
Answer
(B)
shrink since solution is $0.5 \%(\omega / \omega)$
14
The purification method based on the following physical transformation is :
Answer
(D)
Sublimation
15

Identify correct statements :

(A) Primary amines do not give diazonium salts when treated with $\mathrm{NaNO}_2$ in acidic condition.

(B) Aliphatic and aromatic primary amines on heating with $\mathrm{CHCl}_3$ and ethanolic KOH form carbylamines.

(C) Secondary and tertiary amines also give carbylamine test.

(D) Benzenesulfonyl chloride is known as Hinsberg's reagent.

(E) Tertiary amines reacts with benzenesulfonyl chloride very easily.

Choose the correct answer from the options given below :

Answer
(D)
(B) and (D) only
16

Identify the inorganic sulphides that are yellow in colour :

(A) $(NH_4)_2S$

(B) $PbS$

(C) $CuS$

(D) $As_2S_3$

(E) $As_2S_5$

Choose the correct answer from the options given below :

Answer
(A)
(D) and (E) only
17

Consider an elementary reaction

$$ \mathrm{A}(\mathrm{~g})+\mathrm{B}(\mathrm{~g}) \rightarrow \mathrm{C}(\mathrm{~g})+\mathrm{D}(\mathrm{~g}) $$

If the volume of reaction mixture is suddenly reduced to $\frac{1}{3}$ of its initial volume, the reaction rate will become ' $x^{\prime}$ times of the original reaction rate. The value of $x$ is :

Answer
(B)
9
18

Given below are two statements :

Statement I : According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.

Statement II : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.

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

Answer
(A)
Both Statement I and Statement II are false
19

Concentrated nitric acid is labelled as $75 \%$ by mass. The volume in mL of the solution which contains 30 g of nitric acid is ______________.

Given : Density of nitric acid solution is $1.25 \mathrm{~g} / \mathrm{mL}$.

Answer
(A)
32
20
For bacterial growth in a cell culture, growth law is very similar to the law of radioactive decay. Which of the following graphs is most suitable to represent bacterial colony growth ?

Where N - Number of Bacteria at any time, $\mathrm{N}_0$ - Initial number of Bacteria.
Answer
(C)
JEE Main 2025 (Online) 28th January Evening Shift Chemistry - Chemical Kinetics and Nuclear Chemistry Question 8 English Option 3
21
The spin only magnetic moment ( $\mu$ ) value (B.M.) of the compound with strongest oxidising power among $\mathrm{Mn}_2 \mathrm{O}_3, \mathrm{TiO}$ and VO is ____________ B.M. (Nearest integer).
Answer
5
22
Total number of molecules/species from following which will be paramagnetic is __________.

$\mathrm{O}_2, \mathrm{O}_2^{+}, \mathrm{O}_2^{-}, \mathrm{NO}, \mathrm{NO}_2, \mathrm{CO}, \mathrm{K}_2\left[\mathrm{NiCl}_4\right],\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right] \mathrm{Cl}_3, \mathrm{~K}_2\left[\mathrm{Ni}(\mathrm{CN})_4\right]$
Answer
6
23
Electrolysis of 600 mL aqueous solution of NaCl for 5 min changes the pH of the solution to 12 .

The current in Amperes used for the given electrolysis is ___________ . (Nearest integer).
Answer
2
24

Consider the following data :

Heat of formation of $\mathrm{CO}_2(\mathrm{g})=-393.5 \mathrm{~kJ} \mathrm{~mol}{ }^{-1}$

Heat of formation of $\mathrm{H}_2 \mathrm{O}(\mathrm{l})=-286.0 \mathrm{~kJ} \mathrm{~mol}{ }^{-1}$

Heat of combustion of benzene $=-3267.0 \mathrm{~kJ} \mathrm{~mol}^{-1}$

The heat of formation of benzene is __________ $\mathrm{kJ} \mathrm{mol}^{-1}$. (Nearest integer)

Answer
48
25
A group 15 element forms $\mathrm{d} \pi-\mathrm{d} \pi$ bond with transition metals. It also forms hydride, which is a strongest base among the hydrides of other group members that form $d \pi-d \pi$ bond.

The atomic number of the element is _______ .
Answer
15