JEE MAIN - Chemistry (2024 - 31st January Evening Shift)

1

Major product of the following reaction is -

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Hydrocarbons Question 30 English

Answer
(D)
JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Hydrocarbons Question 30 English Option 4
2
$$\mathrm{A}_{(\mathrm{g})} \rightleftharpoons \mathrm{B}_{(\mathrm{g})}+\frac{\mathrm{C}}{2}(\mathrm{g})$$ The correct relationship between $$\mathrm{K}_{\mathrm{P}}, \alpha$$ and equilibrium pressure $$\mathrm{P}$$ is
Answer
(B)
$$K_P=\frac{\alpha^{3 / 2} P^{1 / 2}}{(2+\alpha)^{1 / 2}(1-\alpha)}$$
3

Identify major product 'P' formed in the following reaction.

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 40 English

Answer
(C)
JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 40 English Option 3
4

Given below are two statements:

Statement I : Group 13 trivalent halides get easily hydrolyzed by water due to their covalent nature.

Statement II : $$\mathrm{AlCl}_3$$ upon hydrolysis in acidified aqueous solution forms octahedral $$\left[\mathrm{Al}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{3+}$$ ion.

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
5

The azo-dye $$(Y)$$ formed in the following reactions is

Sulphanilic acid $$+\mathrm{NaNO}_2+\mathrm{CH}_3 \mathrm{COOH} \rightarrow \mathrm{X}$$.

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Compounds Containing Nitrogen Question 38 English

Answer
(C)
JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Compounds Containing Nitrogen Question 38 English Option 3
6

Given below are two statements:

Statement I : $$\mathrm{S}_8$$ solid undergoes disproportionation reaction under alkaline conditions to form $$\mathrm{S}^{2-}$$ and $$\mathrm{S}_2 \mathrm{O}_3{ }^{2-}$$.

Statement II : $$\mathrm{ClO}_4^{-}$$ can undergo disproportionation reaction under acidic condition.

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

Answer
(A)
Statement I is correct but statement II is incorrect
7
Identify structure of 2,3-dibromo-1-phenylpentane.
Answer
(C)
JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Basics of Organic Chemistry Question 60 English Option 3
8

Choose the correct statements from the following

A. All group 16 elements form oxides of general formula $$\mathrm{EO}_2$$ and $$\mathrm{EO}_3$$, where $$\mathrm{E}=\mathrm{S}, \mathrm{Se}, \mathrm{Te}$$ and $$\mathrm{Po}$$. Both the types of oxides are acidic in nature.

B. $$\mathrm{TeO}_2$$ is an oxidising agent while $$\mathrm{SO}_2$$ is reducing in nature.

C. The reducing property decreases from $$\mathrm{H}_2 \mathrm{~S}$$ to $$\mathrm{H}_2$$ Te down the group.

D. The ozone molecule contains five lone pairs of electrons.

Choose the correct answer from the options given below:

Answer
(A)
A and B only
9

The correct order of reactivity in electrophilic substitution reaction of the following compounds is :

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Basics of Organic Chemistry Question 59 English

Answer
(B)
B > A > C > D
10

Choose the correct statements from the following

A. $$\mathrm{Mn}_2 \mathrm{O}_7$$ is an oil at room temperature

B. $$\mathrm{V}_2 \mathrm{O}_4$$ reacts with acid to give $$\mathrm{VO}_2{ }^{2+}$$

C. $$\mathrm{CrO}$$ is a basic oxide

D. $$\mathrm{V}_2 \mathrm{O}_5$$ does not react with acid

Choose the correct answer from the options given below :

Answer
(C)
A and C only
11
Select the option with correct property -
Answer
(D)
$$\left[\mathrm{Ni}(\mathrm{CO})_4\right]$$ Diamagnetic, $$\left[\mathrm{NiCl}_4\right]^{2-}$$ Paramagnetic
12
Which of the following is least ionic?
Answer
(D)
AgCl
13
The four quantum numbers for the electron in the outer most orbital of potassium (atomic no. 19) are
Answer
(B)
$$\mathrm{n}=4, l=0, \mathrm{~m}=0, s=+\frac{1}{2}$$
14

Identify the name reaction.

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 39 English

Answer
(C)
Gatterman - Koch Reaction
15

Consider the following elements.

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Periodic Table & Periodicity Question 38 English

Which of the following is/are true about $$\mathrm{A}^{\prime}, \mathrm{B}^{\prime}, \mathrm{C}^{\prime}$$ and $$\mathrm{D}^{\prime}$$ ?

A. Order of atomic radii: $$\mathrm{B}^{\prime}<\mathrm{A}^{\prime}<\mathrm{D}^{\prime}<\mathrm{C}^{\prime}$$

B. Order of metallic character: $$\mathrm{B}^{\prime}<\mathrm{A}^{\prime}<\mathrm{D}^{\prime}<\mathrm{C}^{\prime}$$

C. Size of the element: $$\mathrm{D}^{\prime}<\mathrm{C}^{\prime}<\mathrm{B}^{\prime}<\mathrm{A}^{\prime}$$

D. Order of ionic radii: $$\mathrm{B}^{\prime+}<\mathrm{A}^{1^{+}}<\mathrm{D}^{\prime+}<\mathrm{C}^{+}$$

Choose the correct answer from the options given below :

Answer
(D)
A, B and D only
16
The fragrance of flowers is due to the presence of some steam volatile organic compounds called essential oils. These are generally insoluble in water at room temperature but are miscible with water vapour in vapour phase. A suitable method for the extraction of these oils from the flowers is -
Answer
(B)
steam distillation
17

Identify A and B in the following reaction sequence.

JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Haloalkanes and Haloarenes Question 32 English

Answer
(C)
JEE Main 2024 (Online) 31st January Evening Shift Chemistry - Haloalkanes and Haloarenes Question 32 English Option 3
18

Match List I with List II

List - I
(Complex ion)
List - II
(Electronic Configuration)
(A) $$\mathrm{[Cr(H_2O)_6]^{3+}}$$ (I) $$t_{2 g}{ }^2 e_g^0$$
(B) $$\left[\mathrm{Fe}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{3+}$$ (II) $$t_{2 g}{ }^3 e_g{ }^0$$
(C) $$\left[\mathrm{Ni}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}$$ (III) $$t_{2 g}{ }^3 e_g{ }^2$$
(D) $$\left[\mathrm{V}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{3+}$$ (IV) $$t_{2 g}{ }^6 e_g^2$$

Choose the correct answer from the options given below:

Answer
(C)
A-II, B-III, C-IV, D-I
19

Given below are two statements :

Statement I : Aniline reacts with con. $$\mathrm{H}_2 \mathrm{SO}_4$$, followed by heating at $$453-473 \mathrm{~K}$$ gives $$\mathrm{p}$$-aminobenzene sulphonic acid, which gives blood red colour in the 'Lassaigne's test'.

Statement II : In Friedel - Craft's alkylation and acylation reactions, aniline forms salt with the $$\mathrm{AlCl}_3$$ catalyst. Due to this, nitrogen of aniline aquires a positive charge and acts as deactivating group.

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 true
20

A sample of $$\mathrm{CaCO}_3$$ and $$\mathrm{MgCO}_3$$ weighed $$2.21 \mathrm{~g}$$ is ignited to constant weight of $$1.152 \mathrm{~g}$$. The composition of mixture is :

(Given molar mass in $$\mathrm{g} \mathrm{~mol}^{-1} \mathrm{CaCO}_3: 100, \mathrm{MgCO}_3: 84$$)

Answer
(B)
$$1.187 \mathrm{~g} \mathrm{~CaCO}_3+1.023 \mathrm{~g} \mathrm{~MgCO}_3$$
21
From the vitamins $$\mathrm{A}, \mathrm{B}_1, \mathrm{~B}_6, \mathrm{~B}_{12}, \mathrm{C}, \mathrm{D}, \mathrm{E}$$ and $$\mathrm{K}$$, the number of vitamins that can be stored in our body is _________.
Answer
5
22

A diatomic molecule has a dipole moment of $$1.2 \mathrm{~D}$$. If the bond distance is $$1 \mathrm{~A}^{\circ}$$, then fractional charge on each atom is _________ $$\times 10^{-1}$$ esu.

(Given $$1 \mathrm{~D}=10^{-18}$$ esucm)

Answer
0
23
Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is ________.
Answer
6
24
In the reaction of potassium dichromate, potassium chloride and sulfuric acid (conc.), the oxidation state of the chromium in the product is $$(+)$$ _________.
Answer
6
25
The values of conductivity of some materials at $298.15 \mathrm{~K}^{-1} ~\text{in} ~\mathrm{Sm}^{-1}$ are $2.1 \times 10^3$,

$1.0 \times 10^{-16}, 1.2 \times 10,3.91,1.5 \times 10^{-2}, 1 \times 10^{-7}, 1.0 \times 10^3$.

The number of conductors among the materials is _____________.
Answer
4
26
A compound $$(x)$$ with molar mass $$108 \mathrm{~g} \mathrm{~mol}^{-1}$$ undergoes acetylation to give product with molar mass $$192 \mathrm{~g} \mathrm{~mol}^{-1}$$. The number of amino groups in the compound $$(x)$$ is ___________.
Answer
2
27
Number of moles of $$\mathrm{H}^{+}$$ ions required by $$1 \mathrm{~mole}$$ of $$\mathrm{MnO}_4^{-}$$ to oxidise oxalate ion to $$\mathrm{CO}_2$$ is _________.
Answer
8
28

If 5 moles of an ideal gas expands from $$10 \mathrm{~L}$$ to a volume of $$100 \mathrm{~L}$$ at $$300 \mathrm{~K}$$ under isothermal and reversible condition then work, $$\mathrm{w}$$, is $$-x \mathrm{~J}$$. The value of $$x$$ is __________.

(Given R = 8.314 J K$$^{-1}$$ mol$$^{-1}$$)

Answer
28721
29

The molarity of $$1 \mathrm{~L}$$ orthophosphoric acid $$\left(\mathrm{H}_3 \mathrm{PO}_4\right)$$ having $$70 \%$$ purity by weight (specific gravity $$1.54 \mathrm{~g} \mathrm{~cm}^{-3}$$) is __________ $$\mathrm{M}$$.

(Molar mass of $$\mathrm{H}_3 \mathrm{PO}_4=98 \mathrm{~g} \mathrm{~mol}^{-1}$$)

Answer
11
30
$$\mathrm{r}=\mathrm{k}[\mathrm{A}]$$ for a reaction, $$50 \%$$ of $$\mathrm{A}$$ is decomposed in 120 minutes. The time taken for $$90 \%$$ decomposition of $$\mathrm{A}$$ is _________ minutes.
Answer
399