JEE MAIN - Chemistry (2023 - 25th January Evening Shift)

1

'A' in the given reaction is

JEE Main 2023 (Online) 25th January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 62 English

Answer
(D)
JEE Main 2023 (Online) 25th January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 62 English Option 4
2
When the hydrogen ion concentration [H$$^+$$] changes by a factor of 1000, the value of pH of the solution __________
Answer
(C)
decreases by 3 units
3

Match List I with List II

List I (Amines) List II ($$\mathrm{pK_b}$$)
A. Aniline I. 3.25
B. Ethanamine II. 3.00
C. N-Ethylethanamine III. 9.38
D. N, N-Diethylethanamine IV. 3.29

Choose the correct answer from the options given below :

Answer
(C)
A-III, B-IV, C-II, D-I
4
What is the mass ratio of ethylene glycol ($$\mathrm{C_2H_6O_2}$$, molar mass = 62 g/mol) required for making 500 g of 0.25 molal aqueous solution and 250 mL of 0.25 molar aqueous solution?
Answer
(C)
2 : 1
5

Find out the major product from the following reaction.

JEE Main 2023 (Online) 25th January Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 49 English

Answer
(D)
JEE Main 2023 (Online) 25th January Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 49 English Option 4
6
The isomeric deuterated bromide with molecular formula $$\mathrm{C_4H_8DBr}$$ having two chiral carbon atoms is
Answer
(C)
2 - Bromo - 3 - deuterobutane
7

Match List I with List II

List I
Isomeric pairs
List II
Type of isomers
A. Propanamine and N-Methylethanamine I. Metamers
B. Hexan-2-one and Hexan-3-one II. Positional isomers
C. Ethanamide and Hydroxyethanimine III. Functional isomers
D. o-nitrophenol and p-nitrophenol IV. Tautomers

Choose the correct answer from the options given below :

Answer
(A)
A-III, B-I, C-IV, D-II
8

A. Ammonium salts produce haze in atmosphere.

B. Ozone gets produced when atmospheric oxygen reacts with chlorine radicals.

C. Polychlorinated biphenyls act as cleansing solvents.

D. 'Blue baby' syndrome occurs due to the presence of excess of sulphate ions in water.

Choose the correct answer from the options given below :

Answer
(D)
A and C only
9

Statement I : Dipole moment is a vector quantity and by convention it is depicted by a small arrow with tail on the negative centre and head pointing towards the positive centre.

Statement II : The crossed arrow of the dipole moment symbolizes the direction of the shift of charges in the molecules.

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

Answer
(B)
Statement I is incorrect but Statement II is correct
10

Match List I with List II

List I
Coordination entity
List II
Wavelength of light absorbed in nm
A. $$\mathrm{[CoCl(NH_3)_5]^{2+}}$$ I. 310
B. $$\mathrm{[Co(NH_3)_6]^{3+}}$$ II. 475
C. $$\mathrm{[Co(CN)_6]^{3-}}$$ III. 535
D. $$\mathrm{[Cu(H_2O)_4]^{2+}}$$ IV. 600

Choose the correct answer from the options given below :

Answer
(B)
A-III, B-II, C-I, D-IV
11
A chloride salt solution acidified with dil.HNO$$_3$$ gives a curdy white precipitate, [A], on addition of AgNO$$_3$$. [A] on treatment with NH$$_4$$OH gives a clear solution B. A and B are respectively :
Answer
(B)
$$\mathrm{AgCl~\&~[Ag(NH_3)_2]Cl}$$
12

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Butylated hydroxy anisole when added to butter increases its shelf life.

Reason R : Butylated hydroxy anisole is more reactive towards oxygen than food.

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

Answer
(C)
Both A and R are correct and R is the correct explanation of A
13
Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from :
Answer
(C)
+ 6 to + 3
14

28.0 L of CO$$_2$$ is produced on complete combustion of 16.8 L gaseous mixture of ethene and methane at 25$$^\circ$$C and 1 atm. Heat evolved during the combustion process is ___________ kJ.

Given : $$\mathrm{\Delta H_c~(CH_4)=-900~kJ~mol^{-1}}$$

$$\mathrm{\Delta H_c~(C_2H_4)=-1400~kJ~mol^{-1}}$$

Answer
847
15

The number of pairs of the solutions having the same value of the osmotic pressure from the following is _________.

(Assume 100% ionization)

A. 0.500 $$\mathrm{M~C_2H_5OH~(aq)}$$ and 0.25 $$\mathrm{M~KBr~(aq)}$$

B. 0.100 $$\mathrm{M~K_4[Fe(CN)_6]~(aq)}$$ and 0.100 $$\mathrm{M~FeSO_4(NH_4)_2SO_4~(aq)}$$

C. 0.05 $$\mathrm{M~K_4[Fe(CN)_6]~(aq)}$$ and 0.25 $$\mathrm{M~NaCl~(aq)}$$

D. 0.15 $$\mathrm{M~NaCl~(aq)}$$ and 0.1 $$\mathrm{M~BaCl_2~(aq)}$$

E. 0.02 $$\mathrm{M~KCl.MgCl_2.6H_2O~(aq)}$$ and 0.05 $$\mathrm{M~KCl~(aq)}$$

Answer
4
16

A first order reaction has the rate constant, $$\mathrm{k=4.6\times10^{-3}~s^{-1}}$$. The number of correct statement/s from the following is/are __________

Given : $$\mathrm{\log3=0.48}$$

A. Reaction completes in 1000 s.

B. The reaction has a half-life of 500 s.

C. The time required for 10% completion is 25 times the time required for 90% completion.

D. The degree of dissociation is equal to ($$\mathrm{1-e^{-kt}}$$)

E. The rate and the rate constant have the same unit.

Answer
1
17

$$Pt(s)|{H_2}(g)(1\,bar)|{H^ + }(aq)(1\,M)||{M^{3 + }}(aq),{M^ + }(aq)|Pt(s)$$

The $$\mathrm{E_{cell}}$$ for the given cell is 0.1115 V at 298 K when $${{\left[ {{M^ + }(aq)} \right]} \over {\left[ {{M^{3 + }}(aq)} \right]}} = {10^a}$$

The value of $$a$$ is ____________

Given : $$\mathrm{E_{{M^{3 + }}/{M^ + }}^\theta = 0.2}$$ V

$${{2.303RT} \over F} = 0.059V$$

Answer
3
18

The number of given orbitals which have electron density along the axis is _________

$$\mathrm{p_x,p_y,p_z,d_{xy},d_{yz},d_{xz},d_{z^2},d_{x^2-y^2}}$$

Answer
5
19
Total number of moles of AgCl precipitated on addition of excess of AgNO$$_3$$ to one mole each of the following complexes $$\mathrm{[Co(NH_3)_4Cl_2]Cl,[Ni(H_2O)_6]Cl_2,[Pt(NH_3)_2Cl_2]}$$ and $$\mathrm{[Pd(NH_3)_4]Cl_2}$$ is ___________.
Answer
5
20

Number of compounds giving (i) red colouration with ceric ammonium nitrate and also (ii) positive iodoform test from the following is ___________

JEE Main 2023 (Online) 25th January Evening Shift Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 63 English

Answer
3
21
Number of hydrogen atoms per molecule of a hydrocarbon A having 85.8% carbon is __________

(Given : Molar mass of A = 84 g mol$$^{-1}$$)
Answer
12