JEE MAIN - Chemistry (2024 - 9th April Morning Shift)

1

Identify the product A and product B in the following set of reactions.

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Hydrocarbons Question 22 English

Answer
(B)
JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Hydrocarbons Question 22 English Option 2
2

The molar conductivity for electrolytes $$A$$ and $$B$$ are plotted against $$C^{3 / 2}$$ as shown below. Electrolytes $$A$$ and $$B$$ respectively are:

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Electrochemistry Question 28 English

Answer
(B)
A - weak electrolyte $$\quad$$ B - strong electrolyte
3

Given below are two statements :

Statement (I) : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.

Statement (II) : $$\mathrm{p} \pi-\mathrm{p} \pi$$ bond formation is more prevalent in second period elements over other periods.

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

Answer
(C)
Statement I is incorrect but Statement II is correct
4

$$0.05 \mathrm{M} \mathrm{~CuSO}_4$$ when treated with $$0.01 \mathrm{M} \mathrm{~K}_2 \mathrm{Cr}_2 \mathrm{O}_7$$ gives green colour solution of $$\mathrm{Cu}_2 \mathrm{Cr}_2 \mathrm{O}_7$$. The two solutions are separated as shown below : [SPM : Semi Permeable Membrane]

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Solutions Question 16 English

Due to osmosis :

Answer
(C)
Molarity of $$\mathrm{CuSO}_4$$ solution is lowered.
5

Identify major product "X" formed in the following reaction :

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 28 English

Answer
(A)
JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 28 English Option 1
6
The $$\mathrm{F}^{-}$$ ions make the enamel on teeth much harder by converting hydroxyapatite (the enamel on the surface of teeth) into much harder fluoroapatite having the formula.
Answer
(A)
$$\left[3\left(\mathrm{Ca}_3\left(\mathrm{PO}_4\right)_2\right) \cdot \mathrm{CaF}_2\right]$$
7

Identify the incorrect statements regarding primary standard of titrimetric analysis.

(A) It should be purely available in dry form.

(B) It should not undergo chemical change in air.

(C) It should be hygroscopic and should react with another chemical instantaneously and stoichiometrically.

(D) It should be readily soluble in water.

(E) $$\mathrm{KMnO}_4$$ & $$\mathrm{NaOH}$$ can be used as primary standard.

Choose the correct answer from the options given below :

Answer
(A)
(C) and (E) only
8

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 27 English

What is the structure of C?

Answer
(A)
JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 27 English Option 1
9
The electronic configuration of $$\mathrm{Cu}(\mathrm{II})$$ is $$3 \mathrm{~d}^9$$ whereas that of $$\mathrm{Cu}(\mathrm{I})$$ is $$3 \mathrm{~d}^{10}$$. Which of the following is correct?
Answer
(A)
$$\mathrm{Cu}(\mathrm{II})$$ is more stable
10
In which one of the following pairs the central atoms exhibit $$\mathrm{sp}^2$$ hybridization ?
Answer
(A)
$$\mathrm{BF}_3$$ and $$\mathrm{NO}_2^{-}$$
11

Relative stability of the contributing structures is :

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 40 English

Answer
(D)
(I) > (II) > (III)
12
Correct order of basic strength of Pyrrole JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 43 English 1, Pyridine JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 43 English 2 and Piperidine JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 43 English 3 is :
Answer
(D)
Piperidine > Pyridine > Pyrrole
13

For the given compounds, the correct order of increasing $$\mathrm{pK}_{\mathrm{a}}$$ value :

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 41 English

Choose the correct answer from the options given below :

Answer
(B)
(B) $$<(\mathrm{D})<(\mathrm{A})<(\mathrm{C})<(\mathrm{E})$$
14

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

Assertion (A) : Both rhombic and monoclinic sulphur exist as $$\mathrm{S}_8$$ while oxygen exists as $$\mathrm{O}_2$$.

Reason (R) : Oxygen forms $$p \pi-p \pi$$ multiple bonds with itself and other elements having small size and high electronegativity like $$\mathrm{C}, \mathrm{N}$$, which is not possible for sulphur.

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

Answer
(D)
Both $$(\mathbf{A})$$ and $$(\mathbf{R})$$ are correct and $$(\mathbf{R})$$ is the correct explanation of $$(\mathbf{A})$$
15

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

Assertion (A): The total number of geometrical isomers shown by $$[\mathrm{Co}(\mathrm{en})_2 \mathrm{Cl}_2]^{+}$$ complex ion is three.

Reason (R): $$[\mathrm{Co}(\mathrm{en})_2 \mathrm{Cl}_2]^{+}$$ complex ion has an octahedral geometry.

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

Answer
(B)
(A) is not correct but (R) is correct
16
Methods used for purification of organic compounds are based on :
Answer
(C)
nature of compound and presence of impurity.
17

Compare the energies of following sets of quantum numbers for multielectron system.

(A) $$\mathrm{n}=4,1=1$$

(B) $$\mathrm{n}=4,1=2$$

(C) $$\mathrm{n}=3, \mathrm{l}=1$$

(D) $$\mathrm{n}=3,1=2$$

(E) $$\mathrm{n}=4,1=0$$

Choose the correct answer from the options given below :

Answer
(C)
$$ (\mathrm{C})<(\mathrm{E})<(\mathrm{D})<(\mathrm{A})<(\mathrm{B}) $$
18

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

Assertion (A) : $$\mathrm{S}_{\mathrm{N}} 2$$ reaction of $$\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{Br}$$ occurs more readily than the $$\mathrm{S}_{\mathrm{N}} 2$$ reaction of $$\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{Br}$$.

Reason (R) : The partially bonded unhybridized p-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring.

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

Answer
(B)
Both (A) and (R) are correct and (R) is the correct explanation of (A)
19
On reaction of Lead Sulphide with dilute nitric acid which of the following is not formed?
Answer
(D)
Nitrous oxide
20

In the following sequence of reaction, the major products B and C respectively are :

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Haloalkanes and Haloarenes Question 21 English

Answer
(B)
JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Haloalkanes and Haloarenes Question 21 English Option 2
21

The standard reduction potentials at $$298 \mathrm{~K}$$ for the following half cells are given below :

$$\mathrm{Cr}_2 \mathrm{O}_7^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+7 \mathrm{H}_2 \mathrm{O}, \quad \mathrm{E}^{\circ}=1.33 \mathrm{~V}$$

$$\begin{array}{ll} \mathrm{Fe}^{3+}(\mathrm{aq})+3 \mathrm{e}^{-} \rightarrow \mathrm{Fe} & \mathrm{E}^{\circ}=-0.04 \mathrm{~V} \\ \mathrm{Ni}^{2+}(\mathrm{aq})+2 \mathrm{e}^{-} \rightarrow \mathrm{Ni} & \mathrm{E}^{\circ}=-0.25 \mathrm{~V} \\ \mathrm{Ag}^{+}(\mathrm{aq})+\mathrm{e}^{-} \rightarrow \mathrm{Ag} & \mathrm{E}^{\circ}=0.80 \mathrm{~V} \\ \mathrm{Au}^{3+}(\mathrm{aq})+3 \mathrm{e}^{-} \rightarrow \mathrm{Au} & \mathrm{E}^{\circ}=1.40 \mathrm{~V} \end{array}$$

Consider the given electrochemical reactions,

The number of metal(s) which will be oxidized be $$\mathrm{Cr}_2 \mathrm{O}_7^{2-}$$, in aqueous solution is _________.

Answer
3
22

Total number of essential amino acid among the given list of amino acids is ________.

Arginine, Phenylalanine, Aspartic acid, Cysteine, Histidine, Valine, Proline

Answer
4
23

Number of ambidentate ligands among the following is _________.

$$\mathrm{NO}_2^{-}, \mathrm{SCN}^{-}, \mathrm{C}_2 \mathrm{O}_4^{2-}, \mathrm{NH}_3, \mathrm{CN}^{-}, \mathrm{SO}_4^{2-}, \mathrm{H}_2 \mathrm{O} \text {. }$$

Answer
3
24

Number of colourless lanthanoid ions among the following is __________.

$$\mathrm{Eu}^{3+}, \mathrm{Lu}^{3+}, \mathrm{Nd}^{3+}, \mathrm{La}^{3+}, \mathrm{Sm}^{3+}$$

Answer
2
25

The total number of species from the following in which one unpaired electron is present, is _______.

$$\mathrm{N}_2, \mathrm{O}_2, \mathrm{C}_2^{-}, \mathrm{O}_2^{-}, \mathrm{O}_2^{2-}, \mathrm{H}_2^{+}, \mathrm{CN}^{-}, \mathrm{He}_2^{+}$$

Answer
4
26

Given below are two statements :

Statement I : The rate law for the reaction $$A+B \rightarrow C$$ is rate $$(r)=k[A]^2[B]$$. When the concentration of both $$\mathrm{A}$$ and $$\mathrm{B}$$ is doubled, the reaction rate is increased "$$x$$" times.

Statement II : JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Chemical Kinetics and Nuclear Chemistry Question 22 English

The figure is showing "the variation in concentration against time plot" for a "$$y$$" order reaction.

The Value of $$x+y$$ is __________.

Answer
8
27

How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects?

JEE Main 2024 (Online) 9th April Morning Shift Chemistry - Basics of Organic Chemistry Question 42 English

Answer
4
28
When equal volume of $$1 \mathrm{~M} \mathrm{~HCl}$$ and $$1 \mathrm{~M} \mathrm{~H}_2 \mathrm{SO}_4$$ are separately neutralised by excess volume of $$1 \mathrm{M}$$ $$\mathrm{NaOH}$$ solution. $$x$$ and $$y \mathrm{~kJ}$$ of heat is liberated respectively. The value of $$y / x$$ is __________.
Answer
2
29

The heat of solution of anhydrous $$\mathrm{CuSO}_4$$ and $$\mathrm{CuSO}_4 \cdot 5 \mathrm{H}_2 \mathrm{O}$$ are $$-70 \mathrm{~kJ} \mathrm{~mol}^{-1}$$ and $$+12 \mathrm{~kJ} \mathrm{~mol}^{-1}$$ respectively.

The heat of hydration of $$\mathrm{CuSO}_4$$ to $$\mathrm{CuSO}_4 \cdot 5 \mathrm{H}_2 \mathrm{O}$$ is $$-x \mathrm{~kJ}$$. The value of $$x$$ is ________. (nearest integer).

Answer
82
30
Molarity $$(\mathrm{M})$$ of an aqueous solution containing $$x \mathrm{~g}$$ of anhyd. $$\mathrm{CuSO}_4$$ in $$500 \mathrm{~mL}$$ solution at $$32^{\circ} \mathrm{C}$$ is $$2 \times 10^{-1} \mathrm{M}$$. Its molality will be _________ $$\times 10^{-3} \mathrm{~m}$$. (nearest integer). [Given density of the solution $$=1.25 \mathrm{~g} / \mathrm{mL}$$]
Answer
164