JEE MAIN - Chemistry (2023 - 13th April Evening Shift)

1

What happens when methane undergoes combustion in systems A and B respectively?

JEE Main 2023 (Online) 13th April Evening Shift Chemistry - Thermodynamics Question 51 English

Answer
(B)
System A System B
Temperature rises Temperature remains same
2
In the wet tests for detection of various cations by precipitation, $$\mathrm{Ba}^{2+}$$ cations are detected by obtaining precipitate of
Answer
(C)
$$\mathrm{BaCO}_{3}$$
3

Compound $$\mathrm{A}$$ from the following reaction sequence is:

JEE Main 2023 (Online) 13th April Evening Shift Chemistry - Compounds Containing Nitrogen Question 55 English

Answer
(D)
Aniline
4
The total number of stereoisomers for the complex $$\left[\mathrm{Cr}(o x)_{2} \mathrm{ClBr}\right]^{3-}$$ (where $$o x=$$ oxalate) is :
Answer
(B)
3
5

The major product for the following reaction is:

JEE Main 2023 (Online) 13th April Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 42 English

Answer
(B)
JEE Main 2023 (Online) 13th April Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 42 English Option 2
6
The naturally occurring amino acid that contains only one basic functional group in its chemical structure is
Answer
(A)
asparagine
7
Which of the following complexes will exhibit maximum attraction to an applied magnetic field?
Answer
(B)
$$\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$$
8

Given below are two statements :

Statement I : $$\mathrm{SO}_{2}$$ and $$\mathrm{H}_{2} \mathrm{O}$$ both possess V-shaped structure.

Statement II : The bond angle of $$\mathrm{SO}_{2}$$ is less than that of $$\mathrm{H}_{2} \mathrm{O}$$.

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

Answer
(C)
Statement I is correct but Statement II is incorrect
9
The covalency and oxidation state respectively of boron in $$\left[\mathrm{BF}_{4}\right]^{-}$$, are :
Answer
(B)
4 and 3
10

Given below are two statements :

Statement I : Tropolone is an aromatic compound and has $$8 \pi$$ electrons.

Statement II : $$\pi$$ electrons of $$ > \mathrm{C}=\mathrm{O}$$ group in tropolone is involved in aromaticity.

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 false
11

Match List I with List II

1 - Bromopropane is reacted with reagents in List I to give product in List II

LIST I - Reagent LIST II - Product
A. $$\mathrm{KOH}$$ (alc) I. Nitrile
B. $$\mathrm{KCN}$$ (alc) II. Ester
C. $$\mathrm{AgNO_2}$$ III. Alkene
D. $$\mathrm{H_3CCOOAg}$$ IV. Nitroalkane

Choose the correct answer from the options given below:

Answer
(C)
A-III, B-I, C-IV, D-II
12

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

Assertion A : Order of acidic nature of the following compounds is A > B > C.

JEE Main 2023 (Online) 13th April Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 43 English

Reason R : Fluoro is a stronger electron withdrawing group than Chloro group.

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

Answer
(A)
Both A and R are correct but R is NOT the correct explanation of A
13
A(g) $$\to$$ 2B(g) + C(g) is a first order reaction. The initial pressure of the system was found to be 800 mm Hg which increased to 1600 mm Hg after 10 min. The total pressure of the system after 30 min will be _________ mm Hg. (Nearest integer)
Answer
2200
14

$$0.400 \mathrm{~g}$$ of an organic compound $$(\mathrm{X})$$ gave $$0.376 \mathrm{~g}$$ of $$\mathrm{AgBr}$$ in Carius method for estimation of bromine. $$\%$$ of bromine in the compound $$(\mathrm{X})$$ is ___________.

(Given: Molar mass $$\mathrm{AgBr=188~g~mol^{-1}}$$

$$\mathrm{Br}=80 \mathrm{~g} \mathrm{~mol}^{-1}$$)

Answer
40
15

See the following chemical reaction:

$$\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}+\mathrm{XH}^{+}+6 \mathrm{~F}_{e}^{2+} \rightarrow \mathrm{YCr}^{3+}+6 \mathrm{~F}_{e}^{3+}+\mathrm{Z} \mathrm{H}_{2} \mathrm{O}$$

The sum of $$\mathrm{X}, \mathrm{Y}$$ and $$\mathrm{Z}$$ is ___________

Answer
23
16
$$1 \mathrm{~g}$$ of a carbonate $$\left(\mathrm{M}_{2} \mathrm{CO}_{3}\right)$$ on treatment with excess $$\mathrm{HCl}$$ produces $$0.01 \mathrm{~mol}$$ of $$\mathrm{CO}_{2}$$. The molar mass of $$\mathrm{M}_{2} \mathrm{CO}_{3}$$ is __________ $$\mathrm{g} ~\mathrm{mol}^{-1}$$. (Nearest integer)
Answer
100
17
The orbital angular momentum of an electron in $$3 \mathrm{~s}$$ orbital is $$\frac{x h}{2 \pi}$$. The value of $$x$$ is ____________ (nearest integer)
Answer
0
18

Sea water contains $$29.25 \% ~\mathrm{NaCl}$$ and $$19 \% ~\mathrm{MgCl}_{2}$$ by weight of solution. The normal boiling point of the sea water is _____________ $${ }^{\circ} \mathrm{C}$$ (Nearest integer)

Assume $$100 \%$$ ionization for both $$\mathrm{NaCl}$$ and $$\mathrm{MgCl}_{2}$$

Given : $$\mathrm{K}_{\mathrm{b}}\left(\mathrm{H}_{2} \mathrm{O}\right)=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$$

Molar mass of $$\mathrm{NaCl}$$ and $$\mathrm{MgCl}_{2}$$ is 58.5 and 95 $$\mathrm{g} \mathrm{~mol}^{-1}$$ respectively.

Answer
116
19

At $$298 \mathrm{~K}$$, the standard reduction potential for $$\mathrm{Cu}^{2+} / \mathrm{Cu}$$ electrode is $$0.34 \mathrm{~V}$$.

Given : $$\mathrm{K}_{\mathrm{sp}} \mathrm{Cu}(\mathrm{OH})_{2}=1 \times 10^{-20}$$

Take $$\frac{2.303 \mathrm{RT}}{\mathrm{F}}=0.059 \mathrm{~V}$$

The reduction potential at $$\mathrm{pH}=14$$ for the above couple is $$(-) x \times 10^{-2} \mathrm{~V}$$. The value of $$x$$ is ___________

Answer
25
20

20 mL of $$0.1 ~\mathrm{M} ~\mathrm{NaOH}$$ is added to $$50 \mathrm{~mL}$$ of $$0.1 ~\mathrm{M}$$ acetic acid solution. The $$\mathrm{pH}$$ of the resulting solution is ___________ $$\times 10^{-2}$$ (Nearest integer)

Given : $$\mathrm{pKa}\left(\mathrm{CH}_{3} \mathrm{COOH}\right)=4.76$$

$$\log 2=0.30$$

$$\log 3=0.48$$

Answer
458