JEE Main 2025 Jan 22 Shift 1 — Chemistry

Radius of the first excited state of Helium ion is given as :

$a_0 \rightarrow$ radius of first stationary state of hydrogen atom.

A liquid when kept inside a thermally insulated closed vessel at $25°\mathrm{C}$ was mechanically stirred from outside. What will be the correct option for the following thermodynamic parameters ?

Arrange the following solutions in order of their increasing boiling points.

(i) $10^{-4}$ M NaCl (ii) $10^{-4}$ M Urea (iii) $10^{-3}$ M NaCl (iv) $10^{-2}$ M NaCl

A vessel at 1000 K contains $\mathrm{CO_2}$ with a pressure of 0.5 atm. Some of $\mathrm{CO_2}$ is converted into CO on addition of graphite. If total pressure at equilibrium is 0.8 atm, then Kp is :

A solution of aluminium chloride is electrolysed for 30 minutes using a current of 2A. The amount of the aluminium deposited at the cathode is ________.

[Given : molar mass of aluminium and chlorine are $27\ \mathrm{g\ mol^{-1}}$ and $35.5\ \mathrm{g\ mol^{-1}}$ respectively. Faraday constant $= 96500\ \mathrm{C\ mol^{-1}}$]

Which of the following electrolyte can be used to obtain $\mathrm{H_2S_2O_8}$ by the process of electrolysis ?

Which of the following statement is not true for radioactive decay ?

Which of the following electronegativity order is incorrect ?

Match List-I with List-II.

	List-I		List-II
(A)	$\mathrm{Al^{3+}} < \mathrm{Mg^{2+}} < \mathrm{Na^{+}} < \mathrm{F^{-}}$	(I)	Ionisation Enthalpy
(B)	B < C < O < N	(II)	Metallic character
(C)	B < Al < Mg < K	(III)	Electronegativity
(D)	Si < P < S < Cl	(IV)	Ionic radii

Choose the correct answer from the options given below :

Lanthanoid ions with $4f^7$ configuration are :

(A) $\mathrm{Eu^{2+}}$ (B) $\mathrm{Gd^{3+}}$ (C) $\mathrm{Eu^{3+}}$ (D) $\mathrm{Tb^{3+}}$ (E) $\mathrm{Sm^{2+}}$

Choose the correct answer from the options given below :

From the magnetic behaviour of $\mathrm{[NiCl_4]^{2-}}$ (paramagnetic) and $\mathrm{[Ni(CO)_4]}$ (diamagnetic), choose the correct geometry and oxidation state.

In which of the following complexes the CFSE, $\Delta_o$ will be equal to zero ?

The IUPAC name of the following compound is :

$$\mathrm{CH_3-CH(COOH)-CH_2-CH_2-CH(COOCH_3)-CH_3}$$

(COOH on the second carbon and $\mathrm{COOCH_3}$ on the fifth carbon of the hexane chain)

How many different stereoisomers are possible for the given molecule ?

$$\mathrm{CH_3-CH(OH)-CH=CH-CH_3}$$

The incorrect statements regarding geometrical isomerism are :

(A) Propene shows geometrical isomerism. (B) Trans isomer has identical atoms/groups on the opposite sides of the double bond. (C) Cis-but-2-ene has higher dipole moment than trans-but-2-ene. (D) 2-methylbut-2-ene shows two geometrical isomers. (E) Trans-isomer has lower melting point than cis isomer.

Choose the correct answer from the options given below :

Given below are two statements :

Statement I : One mole of propyne reacts with excess of sodium to liberate half a mole of $\mathrm{H_2}$ gas.

Statement II : Four g of propyne reacts with $\mathrm{NaNH_2}$ to liberate $\mathrm{NH_3}$ gas which occupies 224 mL at STP.

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

Given below are two statements :

Statement I : $\mathrm{CH_3-O-CH_2-Cl}$ will undergo $S_N1$ reaction though it is a primary halide.

Statement II : $\mathrm{(CH_3)_3C-CH_2-Cl}$ will not undergo $S_N2$ reaction very easily though it is a primary halide.

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

The products formed in the following reaction sequence are :

benzene ring with $\mathrm{NO_2}$ group (nitrobenzene)

$$\mathrm{C_6H_5NO_2} \xrightarrow{\text{(i) } \mathrm{Br_2}, \text{ AcOH; (ii) Sn, HCl; (iii) } \mathrm{NaNO_2}, \text{ HCl, 273 K; (iv) } \mathrm{C_2H_5OH}} \mathrm{A} + \mathrm{B}$$

Which of the following acids is a vitamin ?

The compounds which give positive Fehling's test are :

(A)

benzaldehyde, $\mathrm{C_6H_5-CHO}$

(B)

acetophenone, $\mathrm{C_6H_5-CO-CH_3}$

(C) $\mathrm{HOCH_2-CO-(CHOH)_3-CH_2-OH}$ (D) $\mathrm{CH_3-CHO}$ (E)

phenylacetaldehyde, $\mathrm{C_6H_5-CH_2-CHO}$

Choose the correct answer from the options given below :

Some $\mathrm{CO_2}$ gas was kept in a sealed container at a pressure of 1 atm and at 273 K. This entire amount of $\mathrm{CO_2}$ gas was later passed through an aqueous solution of $\mathrm{Ca(OH)_2}$. The excess unreacted $\mathrm{Ca(OH)_2}$ was later neutralized with 0.1 M of 40 mL HCl. If the volume of the sealed container of $\mathrm{CO_2}$ was x, then x is ________ $\mathrm{cm^3}$ (nearest integer).

[Given : The entire amount of $\mathrm{CO_2(g)}$ reacted with exactly half the initial amount of $\mathrm{Ca(OH)_2}$ present in the aqueous solution.]

The number of molecules/ions that show linear geometry among the following is ________.

$\mathrm{SO_2}$, $\mathrm{BeCl_2}$, $\mathrm{CO_2}$, $\mathrm{N_3^-}$, $\mathrm{NO_2}$, $\mathrm{F_2O}$, $\mathrm{XeF_2}$, $\mathrm{NO_2^+}$, $\mathrm{I_3^-}$, $\mathrm{O_3}$

$$\mathrm{A} \rightarrow \mathrm{B}$$

The molecule A changes into its isomeric form B by following a first order kinetics at a temperature of 1000 K. If the energy barrier with respect to reactant energy for such isomeric transformation is $191.48\ \mathrm{kJ\ mol^{-1}}$ and the frequency factor is $10^{20}$, the time required for $50\%$ molecules of A to become B is ________ picoseconds (nearest integer). $[\mathrm{R} = 8.314\ \mathrm{J\ K^{-1}\ mol^{-1}}]$

In Carius method for estimation of halogens, 180 mg of an organic compound produced 143.5 mg of AgCl. The percentage composition of chlorine in the compound is ________ %.

(Given : molar mass in $\mathrm{g\ mol^{-1}}$ of Ag : 108, Cl : 35.5)

Consider the following sequence of reactions :

benzene ring with $\mathrm{NO_2}$ group (nitrobenzene)

$$\mathrm{C_6H_5NO_2} \xrightarrow{\text{(i) Sn + HCl; (ii) } \mathrm{NaNO_2}, \text{ HCl, } 0°\mathrm{C}\text{; (iii) } \mathrm{Cu_2Cl_2}\text{; (iv) Na, Ether}} \mathrm{A}\ (\text{Product})$$

Molar mass of the product (A) formed is ________ $\mathrm{g\ mol^{-1}}$.