List of top Chemistry Questions

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

An aqueous solution of hydrazine (N₂H₄) is electrochemically oxidized by O₂, thereby releasing chemical energy in the form of electrical energy. One of the products generated from the electrochemical reaction is N₂(g).
Choose the correct statement(s) about the above process

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.
The number of zinc ions present in the molecular formula of $ Q $ is:

Vessel-1 contains w₂ g of a non-volatile solute X dissolved in w₁ g of water. Vessel-2 contains w₂ g of another non-volatile solute Y dissolved in w₁ g of water. Both the vessels are at the same temperature and pressure. The molar mass of X is 80% of that of Y. The van’t Hoff factor for X is 1.2 times of that of Y for their respective concentrations.
The elevation of boiling point for solution in Vessel-1 is _____ % of the solution in Vessel-2.

At room temperature, disproportionation of an aqueous solution of in situ generated nitrous acid (HNO₂) gives the species

A closed vessel contains 10 g of an ideal gas X at 300 K, which exerts 2 atm pressure. At the same temperature, 80 g of another ideal gas Y is added to it and the pressure becomes 6 atm. The ratio of root mean square velocities of X and Y at 300 K is

The option(s) in which at least three molecules follow Octet Rule is(are)

Consider the following reaction,
$2H_2(g) + 2NO(g) \rightarrow N_2(g) + 2H_2O(g)$
which follows the mechanism given below:
$2NO(g)\underset{k_{-1}}{\stackrel{k_1}{\rightleftharpoons}} N_2O_2(g)$ (fast equilibrium)
$N_2O_2(g)+H_2(g) \xrightarrow[]{K_2}N_2O(g)+H_2O$ (slow reaction)
$N_2O(g)+H_2(g) \xrightarrow[]{K_3}N_2(g)+H_2O$ (fast reaction)
The order of the reaction is________

Consider the following volume−temperature (V−T) diagram for the expansion of 5 moles of an ideal monoatomic gas.

Considering only P-V work is involved, the total change in enthalpy (in Joule) for the transformation of state in the sequence X→Y→Z is ______.
[Use the given data: Molar heat capacity of the gas for the given temperature range, C_V,_m = 12 J K⁻¹mol⁻¹ and gas constant, R=8.3 JK⁻¹ mol⁻¹]

Aspartame, an artificial sweetener, is a dipeptide aspartyl phenylalanine methyl ester. The structure of aspartame is

Based on VSEPR model, match the xenon compounds given in List-I with the corresponding geometries and the number of lone pairs on xenon given in List-II and choose the correct option.

List I		List II
(P)	XeF₂	(1)	Trigonal bipyramidal and two lone pair of electrons
(Q)	XeF₄	(2)	Tetrahedral and one lone pair of electrons
(R)	XeO₃	(3)	Octahedral and two lone pair of electrons
(S)	XeO₃F₂	(4)	Trigonal bipyramidal and no lone pair of electrons
		(5)	Trigonal bipyramidal and three lone pair of electrons

In the following reaction sequence, the major product P is formed.

Glycerol reacts completely with excess P in the presence of an acid catalyst to form Q. Reaction of Q with excess NaOH followed by the treatment with CaCl₂ yields Ca-soap R, quantitatively. Starting with one mole of Q, the amount of R produced in gram is ______.
[Given, atomic weight: H = 1, C = 12, N = 14, O = 16, Na = 23, Cl = 35, Ca = 40]

Among the following, the correct statement(s) for electrons in an atom is(are)

In a conductometric titration, small volume of titrant of higher concentration is added stepwise to a larger volume of titrate of much lower concentration, and the conductance is measured after each addition.
The limiting ionic conductivity (Λ0) values (in mS m²mol⁻¹ ) for different ions in aqueous solutions are given below:

Ions	Ag⁺	K⁺	Na⁺	H⁺	$\text{NO}_{3}^{-}$	Cl^-	$\text{SO}^{2-}_{4}$	OH^-	CH₃COO^-
$\Lambda_0$	6.2	7.4	5.0	35.0	7.2	7.6	16.0	19.9	4.1

For different combinations of titrates and titrants given in List-I, the graphs of 'conductance' versus ‘volume of titrant’ are given in List-II.
Match each entry in List-I with the appropriate entry in List-II and choose the correct option.

Among the following complexes, the total number of diamagnetic species is ______.
[Mn(NH₃)₆]³⁺, [MnCl₆]³⁻, [FeF₆]³⁻, [CoF₆]³⁻, [Fe(NH₃)₆]³⁺, and [Co(en)₃]³⁺[Given, atomic number: Mn = 25, Fe = 26, Co = 27;
en = H₂NCH₂CH₂NH₂]

Among V(CO)₆, Cr(CO)₅, Cu(CO)₃, Mn(CO)₅, Fe(CO)₅, [Co(CO)₃]^3-, [Cr(CO)₄]^4-, and Ir(CO)₃, the total number of species isoelectronic with Ni(CO)₄ is _________.
[Given, atomic number: V = 23, Cr=24, Mn 25, Fe 26, Co 27, Ni 28, Cu = 29, Ir = 77]

List-I contains various reaction sequences and List-II contains different phenolic compounds. Match each entry in List-I with the appropriate entry in List-II and choose the correct option.

Reaction of iso-propylbenzene with O₂ followed by the treatment with H₃O⁺ forms phenol and a by-product P. Reaction of P with 3 equivalents of Cl₂ gives compound Q. Treatment of Q with Ca(OH)₂ produces compound R and calcium salt S.
The correct statement(s) regarding P, Q, R and S is(are)

Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. NaOH solution, gives P and Q. Compound P does not give Tollens' test, whereas Q on acidification gives positive Tollens' test. Treatment of P with excess cyclohexanone in the presence of catalytic amount of p-toluenesulfonic acid (PTSA) gives product R.
Sum of the number of methylene groups (-CH2-) and oxygen atoms in R is _______

List-I contains various reaction sequences and List-II contains the possible products. Match each entry in List-I with the appropriate entry in List-II and choose the correct option.

Among the following options, select the option in which each complex in
Set-I shows geometrical isomerism and the two complexes in
Set-II are ionization isomers of each other.
[en = H₂NCH₂CH₂NH₂]

Number of metal ions characterized by flame test among the following is _______.
$\text{Sr}^{2+}, \text{Ba}^{2+}, \text{Ca}^{2+}, \text{Cu}^{2+}, \text{Zn}^{2+}, \text{Co}^{2+}, \text{Fe}^{2+}$

In the following pair of compounds, which compound undergoes an $\text{S}_{N}$2 reaction faster and why?

If an iron (III) complex with the formula \[\left[ \text{Fe}(\text{NH}_3)_x (\text{CN})_y \right]^-\]has no electron in its $ e_g $ orbital, then the value of $ x + y $ is:

$\text{Reaction of aniline with conc. HNO}_3 \text{ and conc. H}_2\text{SO}_4 \text{ at 298 K will produce 47\% of:}$

List I		List II
(P)	Titrate: KCl Titrant: AgNO₃	(1)
(Q)	Titrate: AgNO₃ Titrant: KCl	(2)
(R)	Titrate: NaOH Titrant: HCl	(3)
(S)	Titrate: NaOH Titrant: CH₃COOH	(4)
		(5)