JEE Main 2024 Apr 5 Shift 1 — Chemistry

The incorrect postulates of the Dalton's atomic theory are :

(A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when atoms of different element combine in a fixed ratio. (D) All the atoms of given element have different properties including mass. (E) Chemical reactions involve reorganisation of atoms.

Choose the correct answer from the options given below :

Number of $\sigma$ and $\pi$ bonds present in ethylene molecule is respectively :

The following reaction occurs in the Blast furnance where iron ore is reduced to iron metal

$$\mathrm{Fe_2O_{3(s)} + 3CO_{(g)} \rightleftharpoons Fe_{(l)} + 3CO_{2(g)}}$$

Using the Le-chatelier's principle, predict which one of the following will not disturb the equilibrium.

The reaction at cathode in the cells commonly used in clocks involves.

Molar ionic conductivities of divalent cation and anion are $57~\mathrm{S~cm^2~mol^{-1}}$ and $73~\mathrm{S~cm^2~mol^{-1}}$ respectively. The molar conductivity of solution of an electrolyte with the above cation and anion will be :

The statement(s) that are correct about the species $\mathrm{O^{2-}}$, $\mathrm{F^-}$, $\mathrm{Na^+}$ and $\mathrm{Mg^{2+}}$.

(A) All are isoelectronic (B) All have the same nuclear charge (C) $\mathrm{O^{2-}}$ has the largest ionic radii (D) $\mathrm{Mg^{2+}}$ has the smallest ionic radii

Choose the most appropriate answer from the options given below :

Given below are two statements :

Statement I : In group 13, the stability of $+1$ oxidation state increases down the group.

Statement II : The atomic size of gallium is greater than that of aluminium.

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

The number of neutrons present in the more abundant isotope of boron is '$x$'. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is '$y$'. The value of $x + y$ is ________.

The metal that shows highest and maximum number of oxidation state is :

The correct order of ligands arranged in increasing field strength.

Which one of the following complexes will exhibit the least paramagnetic behaviour ?

[Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27]

Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R)

Assertion (A) : Enthalpy of neutralisation of strong monobasic acid with strong monoacidic base is always $-57~\mathrm{kJ~mol^{-1}}$

Reason (R) : Enthalpy of neutralisation is the amount of heat liberated when one mole of $\mathrm{H^+}$ ions furnished by acid combine with one mole of $\mathrm{{}^-OH}$ ions furnished by base to form one mole of water.

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

An organic compound has 42.1% carbon, 6.4% hydrogen and remainder is oxygen. If its molecular weight is 342, then its molecular formula is :

Given below are two statements :

Statement I : Nitration of benzene involves the following step -

$$\mathrm{H{-}\overset{\oplus}{O}(H){-}NO_2 \rightleftharpoons H_2O + \overset{\oplus}{N}O_2}$$

Statement II : Use of Lewis base promotes the electrophilic substitution of benzene.

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

For the Compounds :

(A) $\mathrm{H_3C{-}CH_2{-}O{-}CH_2{-}CH_2{-}CH_3}$ (B) $\mathrm{H_3C{-}CH_2{-}CH_2{-}CH_2{-}CH_3}$ (C) $\mathrm{CH_3{-}CH_2{-}CO{-}CH_2{-}CH_3}$ (D) $\mathrm{H_3C{-}CH(OH){-}CH_2{-}CH_2{-}CH_3}$

The increasing order of boiling point is :

Choose the correct answer from the options given below :

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

Assertion (A) : Cis form of alkene is found to be more polar than the trans form.

Reason (R) : Dipole moment of trans isomer of 2-butene is zero.

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

Given below are two statement :

Statements I : Bromination of phenol in solvent with low polarity such as $\mathrm{CHCl_3}$ or $\mathrm{CS_2}$ requires Lewis acid catalyst.

Statements II : The Lewis acid catalyst polarises the bromine to generate $\mathrm{Br^+}$.

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

Identify compound (Z) in the following reaction sequence.

chlorobenzene (benzene ring with Cl) as starting material

$\mathrm{C_6H_5Cl + NaOH \xrightarrow[300~atm]{623~K} X \xrightarrow{HCl} Y \xrightarrow{Conc.~HNO_3} Z}$

Identify 'A' in the following reaction :

butan-2-one structure

$\mathrm{CH_3{-}CO{-}CH_2{-}CH_3 \xrightarrow{(i)~N_2H_4~;~(ii)~ethylene~glycol/KOH} 'A'}$

Which of the following gives a positive test with ninhydrin ?

The value of Rydberg constant ($\mathrm{R_H}$) is $2.18 \times 10^{-18}$ J. The velocity of electron having mass $9.1 \times 10^{-31}$ kg in Bohr's first orbit of hydrogen atom $=$ ________ $\times 10^{5}~\mathrm{ms^{-1}}$ (nearest integer).

In the lewis dot structure for $\mathrm{NO_2^-}$, total number of valence electrons around nitrogen is ________.

The heat of combustion of solid benzoic acid at constant volume is $-321.30$ kJ at $27\,°\mathrm{C}$. The heat of combustion at constant pressure is $(-321.30 - x\mathrm{R})$ kJ, the value of $x$ is ________.

An artificial cell is made by encapsulating 0.2 M glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a 0.05 M solution of NaCl at 300 K is ________ $\times~10^{-1}$ bar. (nearest integer).

[Given : $\mathrm{R} = 0.083~\mathrm{L~bar~mol^{-1}~K^{-1}}$]

Assume complete dissociation of NaCl

During Kinetic study of reaction $2A + B \rightarrow C + D$, the following results were obtained :

	A [M]	B [M]	initial rate of formation of D
I	0.1	0.1	$6.0 \times 10^{-3}$
II	0.3	0.2	$7.2 \times 10^{-2}$
III	0.3	0.4	$2.88 \times 10^{-1}$
IV	0.4	0.1	$2.40 \times 10^{-2}$

Based on above data, overall order of the reaction is ________.

The spin-only magnetic moment value of the ion among $\mathrm{Ti^{2+}}$, $\mathrm{V^{2+}}$, $\mathrm{Co^{3+}}$ and $\mathrm{Cr^{2+}}$, that acts as strong oxidising agent in aqueous solution is ________ BM (Near integer).

(Given atomic numbers : Ti : 22, V : 23, Cr : 24, Co : 27)

flame diagram with two marked zones — A (upper, outer zone) and B (lower, inner zone)

In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is ________ BM (Nearest integer)

[Given atomic number of Cu = 29, Ni = 28, Mn = 25, Fe = 26]

The number of halobenzenes from the following that can be prepared by Sandmeyer's reaction is ________.

five monosubstituted benzenes — I : $\mathrm{C_6H_5F}$, II : $\mathrm{C_6H_5Cl}$, III : $\mathrm{C_6H_5Br}$, IV : $\mathrm{C_6H_5I}$, V : $\mathrm{C_6H_5At}$

Consider the given chemical reaction sequence :

phenol (benzene ring with OH) as starting material

$\mathrm{Phenol \xrightarrow{Conc.~H_2SO_4} Product~A \xrightarrow{Conc.~HNO_3} Product~B}$

Total sum of oxygen atoms in Product A and Product B are ________.

9.3 g of pure aniline is treated with bromine water at room temperature to give a white precipitate of the product 'P'. The mass of product 'P' obtaind is 26.4 g. The percentage yield is ________ %.