JEE MAIN - Chemistry (2022 - 29th June Evening Shift)

1
Which of the following is the correct plot for the probability density $${\psi ^2}$$ (r) as a function of distance 'r' of the electron from the nucleus for 2s orbital?
Answer
(B)
JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Structure of Atom Question 88 English Option 2
2
Consider the species CH4, NH$$_4^ + $$ and BH$$_4^ - $$. Choose the correct option with respect to the these species.
Answer
(B)
They are isoelectronic and all have tetrahedral structures.
3

4.0 moles of argon and 5.0 moles of PCl5 are introduced into an evacuated flask of 100 litre capacity at 610 K. The system is allowed to equilibrate. At equilibrium, the total pressure of mixture was found to be 6.0 atm. The Kp for the reaction is :

[Given : R = 0.082 L atm K$$-$$1 mol$$-$$1]

Answer
(A)
2.25
4

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 for oxygen is lower than that of nitrogen.

Reason R : The four electrons in 2p orbitals of oxygen experience more electron-electron repulsion.

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

Answer
(B)
Both A and R are are correct but R is NOT the correct explanation of A.
5

Given below are two statements.

$$\bullet$$ Statement I : In CuSO4 . 5H2O, Cu-O bonds are present.

$$\bullet$$ Statement II : In CuSO4 . 5H2O, ligands coordinating with Cu(II) ion are O-and S-based ligands.

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

Answer
(C)
Statement I is correct but Statement II is incorrect.
6
Number of lone pair(s) of electrons on central atom and the shape BrF3 molecule respectively, are
Answer
(C)
2, bent T-shape.
7
Sulphur dioxide is one of the components of polluted air. SO2 is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by SO2 is :
Answer
(D)
2SO2 + O2 + 2H2O $$\to$$ 2H2SO4
8
Which of the following carbocations is most stable?
Answer
(D)
JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Basics of Organic Chemistry Question 128 English Option 4
9

JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Haloalkanes and Haloarenes Question 72 English

The stable carbocation formed in the above reaction is

Answer
(C)
$$C{H_3} - \mathop C\limits^ \oplus H - C{H_3}$$
10
Two isomers (A) and (B) with Molar mass 184 g/mol and elemental composition C, 52.2%; H, 4.9% and Br 42.9% gave benzoic acid and p-bromobenzoic acid, respectively on oxidation with KMnO4. Isomer 'A' is optically active and gives a pale yellow precipitate when warmed with alcoholic AgNO3. Isomer 'A' and 'B' are, respectively
Answer
(C)
JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Haloalkanes and Haloarenes Question 71 English Option 3
11
In Friedel-Crafts alkylation of aniline, one gets
Answer
(D)
positively charged nitrogen at benzene ring.
12
The structure of protein that is unaffected by heating is
Answer
(C)
primary structure
13
A white precipitate was formed when BaCl2 was added to water extract of an inorganic salt. Further, a gas 'X' with characteristic odour was released when the formed white precipitate was dissolved in dilute HCl. The anion present in the inorganic salt is
Answer
(B)
SO32$$-$$
14

A box contains 0.90 g of liquid water in equilibrium with water vapour at 27$$^\circ$$C. The equilibrium vapour pressure of water at 27$$^\circ$$C is 32.0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be __________ litre. [nearest integer]

(Given : R = 0.082 L atm K$$-$$1 mol$$-$$1)

(Ignore the volume of the liquid water and assume water vapours behave as an ideal gas.)

Answer
29
15

2.2 g of nitrous oxide (N2O) gas is cooled at a constant pressure of 1 atm from 310 K to 270 K causing the compression of the gas from 217.1 mL to 167.75 mL. The change in internal energy of the process, $$\Delta$$U is '$$-$$x' J. The value of 'x' is ________. [nearest integer]

(Given : atomic mass of N = 14 g mol$$-$$1 and of O = 16 g mol$$-$$1. Molar heat capacity of N2O is 100 J K$$-$$1 mol$$-$$1)

Answer
195
16
Elevation in boiling point for 1.5 molal solution of glucose in water is 4 K. The depression in freezing point for 4.5 molal solution of glucose in water is 4 K. The ratio of molal elevation constant to molal depression constant (Kb/Kf) is _________.
Answer
3
17

The cell potential for the given cell at 298 K

Pt| H2 (g, 1 bar) | H+ (aq) || Cu2+ (aq) | Cu(s)

is 0.31 V. The pH of the acidic solution is found to be 3, whereas the concentration of Cu2+ is 10$$-$$x M. The value of x is ___________.

(Given : $$E_{C{u^{2 + }}/Cu}^\Theta $$ = 0.34 V and $${{2.303\,RT} \over F}$$ = 0.06 V)

Answer
7
18

The equation

k = (6.5 $$\times$$ 1012s$$-$$1)e$$-$$26000K/T

is followed for the decomposition of compound A. The activation energy for the reaction is ________ kJ mol$$-$$1. [nearest integer]

(Given : R = 8.314 J K$$-$$1 mol$$-$$1)

Answer
216
19
Spin only magnetic moment of [MnBr6]4$$-$$ is _________ B.M. (round off to the closest integer)
Answer
6
20

For the reaction given below :

CoCl3 . xNH3 + AgNO3 (aq) $$\to$$

If two equivalents of AgCl precipitate out, then the value of x will be _____________.

Answer
5
21
The number of chiral alcohol(s) with molecular formula C4H10O is ________.
Answer
2
22

In the given reaction,

JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 84 English

the number of sp2 hybridised carbon(s) in compound 'X' is ________.

Answer
8
23

In the given reaction,

JEE Main 2022 (Online) 29th June Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 104 English

The number of $$\pi$$ electrons present in the product 'P' is _________.

Answer
4