JEE MAIN - Chemistry (2023 - 1st February Morning Shift)

1
Which of the following complex will show largest splitting of d-orbitals?
Answer
(B)
$$[\mathrm{Fe(CN)_6]^{3-}}$$
2

Which of the following are the example of double salt?

A. $$\mathrm{FeSO}_{4} \cdot\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4} \cdot 6 \mathrm{H}_{2} \mathrm{O}$$

B. $$\mathrm{CuSO}_{4}\cdot 4 \mathrm{NH}_{3} \cdot \mathrm{H}_{2} \mathrm{O}$$

C. $$\mathrm{K}_{2} \mathrm{SO}_{4} \cdot \mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3} \cdot 24 \mathrm{H}_{2} \mathrm{O}$$

D. $$\mathrm{Fe}(\mathrm{CN})_{2}\cdot4 \mathrm{KCN}$$

Choose the correct answer :

Answer
(D)
A and C only
3

Highest oxidation state of Mn is exhibited in $$\mathrm{Mn_2O_7}$$. The correct statements about $$\mathrm{Mn_2O_7}$$ are

(A) Mn is tetrahedrally surrounded by oxygen atoms.

(B) Mn is octahedrally surrounded by oxygen atoms.

(C) Contains Mn-O-Mn bridge.

(D) Contains Mn-Mn bond.

Choose the correct answer from the options given below :

Answer
(A)
A and C only
4

The correct representation in six membered pyranose form for the following sugar [X] is

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Biomolecules Question 54 English

Answer
(D)
JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Biomolecules Question 54 English Option 4
5

But-2-yne is reacted separately with one mole of Hydrogen as shown below :

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Hydrocarbons Question 53 English

A. A is more soluble than B.

B. The boiling point & melting point of A are higher and lower than B respectively.

C. A is more polar than B because dipole moment of A is zero.

D. $$\mathrm{Br_2}$$ adds easily to B than A.

Identify the incorrect statements from the options given below :

Answer
(D)
C and D only
6

Resonance in carbonate ion $$\left(\mathrm{CO}_{3}{ }^{2-}\right)$$ is

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Basics of Organic Chemistry Question 98 English

Which of the following is true?

Answer
(D)
$$\mathrm{CO}_{3}{ }^{2-}$$ has a single structure i.e., resonance hybrid of the above three structures.
7

Match List I with List II

List I List II
Test Functional group / Class of Compound
A. Molisch's Test I. Peptide
B. Biuret Test II. Carbohydrate
C. Carbylamine Test III. Primary amine
D. Schiff's Test IV. Aldehyde

Choose the correct answer from the options given below :

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

In the following reaction, 'A' is

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Compounds Containing Nitrogen Question 72 English

Answer
(B)
JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Compounds Containing Nitrogen Question 72 English Option 2
9
A solution of $$\mathrm{FeCl_3}$$ when treated with $$\mathrm{K_4[Fe(CN)_6]}$$ gives a prussium blue precipitate due to the formation of :
Answer
(B)
$$\mathrm{Fe_{4}[Fe(CN)_{6}]_{3}}$$
10
Identify the incorrect option from the following
Answer
(C)
JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Alcohols, Phenols and Ethers Question 56 English Option 3
11

Decreasing order of dehydration of the following alcohols is

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Alcohols, Phenols and Ethers Question 57 English

Answer
(B)
b > d > c > a
12

25 mL of an aqueous solution of KCl was found to require 20 mL of 1 M $$\mathrm{AgNO_3}$$ solution when titrated using $$\mathrm{K_2CrO_4}$$ as an indicator. What is the depression in freezing point of KCl solution of the given concentration? _________ (Nearest integer).

(Given : $$\mathrm{K_f=2.0~K~kg~mol^{-1}}$$)

Assume 1) 100% ionization and 2) density of the aqueous solution as 1 g mL$$^{-1}$$

Answer
3
13

Electrons in a cathode ray tube have been emitted with a velocity of 1000 m s$$^{-1}$$. The number of following statements which is/are $$\underline {\mathrm{true}} $$ about the emitted radiation is ____________.

Given : $$\mathrm{h=6\times10^{-34}~J~s,m_e=9\times10^{-31}~kg}$$.

(A) The de-Broglie wavelength of the electron emitted is 666.67 nm.

(B) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube.

(C) The cathode rays start from cathode and move towards anode.

(D) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube.

Answer
2
14

At what pH, given half cell $$\mathrm{MnO_{4}^{-}(0.1~M)~|~Mn^{2+}(0.001~M)}$$ will have electrode potential of 1.282 V? ___________ (Nearest Integer)

Given $$\mathrm{E_{MnO_4^ - |M{n^{2 + }}}^o}=1.54~\mathrm{V},\frac{2.303\mathrm{RT}}{\mathrm{F}}=0.059\mathrm{V}$$

Answer
3
15
A and B are two substances undergoing radioactive decay in a container. The half life of A is 15 min and that of B is 5 min. If the initial concentration of B is 4 times that of A and they both start decaying at the same time, how much time will it take for the concentration of both of them to be same? _____________ min.
Answer
15
16

At $$25^{\circ} \mathrm{C}$$, the enthalpy of the following processes are given :

$$\mathrm{H_2(g)+O_2(g)}$$ $$\to$$ $$2\mathrm{OH(g)}$$ $$\mathrm{\Delta H^\circ=78~kJ~mol^{-1}}$$
$$\mathrm{H_2(g)+\frac{1}{2}O_2(g)}$$ $$\to$$ $$\mathrm{H_2O(g)}$$ $$\mathrm{\Delta H^\circ=-242~kJ~mol^{-1}}$$
$$\mathrm{H_2(g)}$$ $$\to$$ $$\mathrm{2H(g)}$$ $$\mathrm{\Delta H^\circ=436~kJ~mol^{-1}}$$
$$\frac{1}{2}\mathrm{O_2(g)}$$ $$\to$$ $$\mathrm{O(g)}$$ $$\mathrm{\Delta H^\circ=249~kJ~mol^{-1}}$$

What would be the value of X for the following reaction ? _____________ (Nearest integer)

$$\mathrm{H_2O(g)\to H(g)+OH(g)~\Delta H^\circ=X~kJ~mol^{-1}}$$

Answer
499
17
Sum of oxidation states of bromine in bromic acid and perbromic acid is ___________.
Answer
12
18
Number of isomeric compounds with molecular formula $$\mathrm{C}_{9} \mathrm{H}_{10} \mathrm{O}$$ which (i) do not dissolve in $$\mathrm{NaOH}$$ (ii) do not dissolve in $$\mathrm{HCl}$$. (iii) do not give orange precipitate with 2,4-DNP (iv) on hydrogenation give identical compound with molecular formula $$\mathrm{C}_{9} \mathrm{H}_{12} \mathrm{O}$$ is ____________.
Answer
2
19

The total number of chiral compound/s from the following is ______________.

JEE Main 2023 (Online) 1st February Morning Shift Chemistry - Basics of Organic Chemistry Question 97 English

Answer
2
20

(i) $$\mathrm{X}(\mathrm{g}) \rightleftharpoons \mathrm{Y}(\mathrm{g})+\mathrm{Z}(\mathrm{g}) \quad \mathrm{K}_{\mathrm{p} 1}=3$$

(ii) $$\mathrm{A}(\mathrm{g}) \rightleftharpoons 2 \mathrm{~B}(\mathrm{g}) \quad \mathrm{K}_{\mathrm{p} 2}=1$$

If the degree of dissociation and initial concentration of both the reactants $$\mathrm{X}(\mathrm{g})$$ and $$\mathrm{A}(\mathrm{g})$$ are equal, then the ratio of the total pressure at equilibrium $$\left(\frac{p_{1}}{p_{2}}\right)$$ is equal to $$\mathrm{x}: 1$$. The value of $$\mathrm{x}$$ is _____________ (Nearest integer)

Answer
12
21

The density of $$3 \mathrm{M}$$ solution of $$\mathrm{NaCl}$$ is $$1.0 \mathrm{~g} \mathrm{~mL}^{-1}$$. Molality of the solution is ____________ $$\times 10^{-2} \mathrm{~m}$$. (Nearest integer).

Given: Molar mass of $$\mathrm{Na}$$ and $$\mathrm{Cl}$$ is $$23$$ and $$35.5 \mathrm{~g} \mathrm{~mol}^{-1}$$ respectively.

Answer
364