List of top Chemistry Questions asked in JEE Advanced

The species formed on fluorination of phosphorus pentachloride in a polar organic solvent are:

The option(s) with the correct sequence of reagents for the conversion of P to Q is (are):

An aqueous solution of hydrazine (\(N_2H_4\)) is electrochemically oxidized by \(O_2\), thereby releasing chemical energy in the form of electrical energy. One of the products generated from the electrochemical reaction is \(N_2(g)\). Choose the correct statement(s) about the above process:

According to Bohr's model, the highest kinetic energy is associated with the electron in the:

An organic compound P with molecular formula C₉H₁₈O₂ decolorizes bromine water and also shows positive iodoform test. P on ozonolysis followed by treatment with H₂O₂ gives Q and R. While compound Q shows positive iodoform test, compound R does not give positive iodoform test. Q and R on oxidation with pyridinium chlorochromate (PCC) followed by heating give S and T, respectively. Both S and T show positive iodoform test.
Complete copolymerization of 500 moles of Q and 500 moles of R gives one mole of a single acyclic copolymer U. [Given, atomic mass: H =1, C = 12, O =16]

When potassium iodide is added to an aqueous solution of potassium ferricyanide, a reversible reaction is observed in which a complex P is formed. In a strong acidic medium, the equilibrium shifts completely towards P. Addition of zinc chloride to P in a slightly acidic medium results in a sparingly soluble complex Q.

Among [I₃]⁺ , [SiO₄]^4-, SO₂Cl₂, XeF₂, SF₄, ClF₃, Ni(CO)_4, XeO₂F₂, [PtCl_4]²⁻, XeF₄, and SOCl₂, the total number of species having sp³ hybridised central atom is ______.

The correct molecular orbital diagram for F₂ molecule in the ground state is

On decreasing the 𝑝H from 7 to 2, the solubility of a sparingly soluble salt (MX) of a weak acid (HX) increased from 10⁻⁴ mol L⁻¹ to 10⁻³mol L⁻¹. The 𝑝Ka of HX is

For He⁺, a transition takes place from the orbit of radius 105.8 pm to the orbit of radius 26.45 pm. The wavelength (in nm) of the emitted photon during the transition is ___.
[Use: Bohr radius, a = 52.9 pm, Rydberg constant, 𝑅H = 2.2 × 10⁻¹⁸ J, Planck’s constant, h = 6.6 × 10⁻³⁴ J s, Speed of light, c = 3 × 10⁸ m s⁻¹]

H₂S (5 moles) reacts completely with acidified aqueous potassium permanganate solution. In this reaction, the number of moles of water produced is x, and the number of moles of electrons involved is y. The value of (x + y) is ____.

The stoichiometric reaction of 516 g of dimethyldichlorosilane with water results in a tetrameric cyclic product X in 75% yield. The weight (in g) of X obtained is___. [Use, molar mass (g mol⁻¹): H = 1, C = 12, O = 16, Si = 28, Cl = 35.5]

50 mL of 0.2 molal urea solution (density = 1.012 g mL⁻¹ at 300 K) is mixed with 250 mL of a solution containing 0.06 g of urea. Both solutions were prepared in the same solvent. The osmotic pressure (in Torr) of the resulting solution at 300 K is ___.
[Use: Molar mass of urea = 60 g mol⁻¹ ; gas constant, R = 62 L Torr K⁻¹ mol⁻¹; Assume, Δ_mixH = 0, Δ_mixV = 0]

In the given reaction scheme, P is a phenyl alkyl ether, Q is an aromatic compound; R and S are the major products.

The correct statement about S is

The plot of log 𝑘_𝑓 versus \(\frac{1}{T}\) for a reversible reaction, A (g) ⇌ P (g) is shown.

Pre-exponential factors for the forward and backward reactions are 10¹⁵s^-1 and 10¹¹s^-1 respectively. If the value of log K for the reaction at 500 K is 6, the value of |log kb| at 250K is_________[K = equilibrium constant of the reaction, 𝑘_𝑓 = rate constant of forward reaction, 𝑘_𝑏 = rate constant of backward reaction]

The complex(es), which can exhibit the type of isomerism shown by [Pt(NH₃)₂Br₂], is(are) [en = H₂NCH₂CH₂NH₂]

Match the reactions in List-I with the features of their products in List-II and choose the correct option

A disaccharide X cannot be oxidised by bromine water. The acid hydrolysis of X leads to a laevorotatory solution. The disaccharide X is

The total number of sp2 hybridised carbon atoms in the major product P (a non-heterocyclic compound) of the following reaction is ___.

Match the reactions (in the given stoichiometry of the reactants) in List-I with one of their products given in List-II and choose the correct option.

	List-I		List-II
(P)	P₂O₃ + 3H₂O →	(1)	P(O)(OCH₃)Cl₂
(Q)	P₄ + 3NaOH + 3H₂O →	(2)	H₃PO₃
(R)	PCl₅ + CH₃COOH →	(3)	PH₃
(S)	H₃PO₂ + 2H₂O + 4AgNO₃ →	(4)	POCl₃
		(5)	H₃PO₄

The major products obtained from the reactions in List-II are the reactants for the named reactions mentioned in List-I. Match List-I with List-II and choose the correct option.

In the following reactions, P, Q, R, and S are the major products.

The correct statement(s) about P, Q, R, and S is(are)

One mole of an ideal monoatomic gas undergoes two reversible processes (\(A → B\) and \(B → C\)) as shown in the given figure:

\(A → B\) is an adiabatic process. If the total heat absorbed in the entire process (\(A → B\) and \(B → C\)) is \(R𝑇_2\ ln\ 10\), the value of \(2 log\ 𝑉_3\) is ___ . [Use, molar heat capacity of the gas at constant pressure, \(𝐶_{p,m} = \frac 52R\)]

In the scheme given below, X and Y, respectively, are

Plotting \(\frac{1}{Λ_{m}}\)against \(cΛ_{m}\) for aqueous solutions of a monobasic weak acid (HX) resulted in a straight line with y-axis intercept of P and slope of S. The ratio \(\frac{P}{S}\) is
[\(Λ_{m}\) = molar conductivity,
\(Λ^{o}_{m}\)= limiting molar conductivity,
\(c\) = molar concentration,
\(K_{a}\) = dissociation constant of HX]

	List-I		List-II
(P)	(-)-1-Bromo-2-ethylpentane (single enantiomer)	(1)	Inversion of configuration
(Q)	(-)-2-Bromopentane (single enantiomer)	(2)	Retention of configuration
(R)	(-)-3- Bromo-3-methylhexane (single enantiometer)	(3)	Mixture of enantiomers
(S)	(single enantiometer)	(4)	Mixture of structural isomers
		(5)	Mixture of diastereomers