List of top Chemistry Questions asked in JEE Advanced

For the given close packed structure of a salt made of cation $X$ and anion $Y$ shown below (ions of only one face are shown for clarity), the packing fraction is approximately (packing fraction $=\frac{\text { packing efficiency }}{100}$ )

A mixture of two salts is used to prepare a solution S, which gives the following results:

\(\text{White precipitate(s) only} \underset{\text{Room temperature}}{\overset{\text{Dilute NaOH(aq)}}{\longleftarrow}} \text{S (aq solution of the salts)}\underset{\text{Room temperature}}{\overset{\text{Dilute HCl(aq)}}{\longrightarrow}} \text{White precipitate(s) only}\)
The correct option(s) for the salt mixture is(are)

Among the following, the conformation that corresponds to the most stable conformation of meso-butane-$2,3$-diol is

Some standard electrode potentials at 298 K are given below:
Pb²⁺/Pb –0.13 V
Ni²⁺/Ni –0.24 V
C²⁺/Cd –0.40 V
Fe²⁺/Fe –0.44 V
To a solution containing 0.001 M of X²⁺ and 0.1 M of Y²⁺, the metal rods X and Y are inserted (at 298 K) and connected by a conducting wire. This resulted in the dissolution of X.
The correct combination(s) of X and Y, respectively, is(are)
(Given: Gas constant, R = 8.314 J K^-1 mol^-1, Faraday constant, F = 96500 C mol^-1)

The correct statement(s) related to oxoacids of phosphorous is(are)

For the following reaction;
\(\begin{array}{l}2X + Y\overset{k}{\rightarrow}P\end{array}\)

The rate of reaction is
\(\begin{array}{l}\frac{d[P]}{dt} = k[X]\end{array}\)
Two moles of X are mixed with one mole of Y to make 1.0 L of solution. At 50 s, 0.5 mole of Y is left in the reaction mixture. The correct statement(s) about the reaction is(are). (Use: ln 2 = 0.693)

The pair(s) of complexes wherein both exhibit tetrahedral geometry is(are)
(Note: py = pyridine, Given: Atomic numbers of Fe, Co, Ni and Cu are 26, 27, 28 and 29, respectively)

For the reaction, $X (s) \rightleftharpoons Y (s)+ Z (g)$, the plot of $\ln \frac{p_{ Z }}{p^{0}}$ versus $\frac{10^{4}}{T}$ is given below (in solid line), where $p_{ z }$ is the pressure (in bar) of the gas $Z$ at temperature $T$ and $p^0=1$ bar

 (Given, $\frac{ d (\ln K)}{ d \left(\frac{1}{T}\right)}=-\frac{\Delta H^{0}}{R}$, where the equilibrium constant, $K=\frac{p_{z}}{p^{0}}$ and the gas constant, $R=8314 \,J \,K ^{-1} mol ^{-1}$ ) 
The value of standard enthalpy, $\Delta H^{0}$ (in $kJ\, mol ^{-1}$ ) for the given reaction is ______

The boiling point of water in a $01$ molal silver nitrate solution (solution $A$ ) is $x ^{\circ} C$ To this solution $A$, an equal volume of $01$ molal aqueous barium chloride solution is added to make a new solution $B$ The difference in the boiling points of water in the two solutions $A$ and $B$ is $y \times 10^{-2}{ }^{\circ} C$ (Assume: Densities of the solutions $A$ and $B$ are the same as that of water and the soluble salts dissociate completely Use: Molal elevation constant (Ebullioscopic Constant), $K _{ b }=05 \,K \,kg\, mol ^{-1}$; Boiling point of pure water as $100^{\circ} C$)
The value of $x$ is ______$^{\circ}C$

In the reaction given below, the total number of atoms having sp² hybridization in the major product P is ___.

For the following reaction scheme, percentage yields are given along the arrow: 

$X\, g$ and $y \,g$ are mass of $R$ and $U$, respectively (Use : Molar mass (in $g \,mol^{-1})$ of $H, C$ and $O$ as $1, 12$ and $16$, respectively) The value of $y$ is _______

One mole of an ideal gas at 900 K, undergoes two reversible processes, I followed by II, as shown below. If the work done by the gas in the two processes are the same, the value of \(\ln \frac{v_3}{v_2}\) is _____

(U: internal energy, S: entropy, p: pressure, V: volume, R: gas constant)
(Given: molar heat capacity at constant volume, \(C_v,m\) of the gas is \(\frac{5}{2}\)R)

The amount of energy required to break a bond is the same as the amount of energy released when the same bond is formed. In a gaseous state, the energy required for homolytic cleavage of a bond is called Bond Dissociation Energy (BDE) or Bond Strength. BDE is affected by the s-character of the bond and the stability of the radicals formed. Shorter bonds are typically stronger bonds. BDEs for some bonds are given below:

The reaction of K₃[Fe(CN)₆] with freshly prepared FeSO₄ solution produces a dark blue precipitate called Turnbull’s blue. The reaction of K₄[Fe(CN)₆] with the FeSO₄ solution in the complete absence of air produces a white precipitate X, which turns blue in the air. Mixing the FeSO₄ solution with NaNO₃, followed by slow addition of concentrated H₂SO₄ through the side of the test tube produces a brown ring.

A sample (5.6 g) containing iron is completely dissolved in cold dilute HCl to prepare a 250 mL of solution. Titration of 25.0 mL of this solution requires 12.5 mL of 0.03 M KMnO₄ solution to reach the endpoint. Number of moles of Fe²⁺ present in 250 mL solution is x × 10^–2 (consider complete dissolution of FeCl₂). The amount of iron present in the sample is y% by weight.
(Assume: KMnO₄ reacts only with Fe²⁺ in the solution Use: Molar mass of iron as 56 g mol^–1)

The reaction of x g of Sn with HCl quantitatively produced a salt. The entire amount of the salt reacted with y g of nitrobenzene in the presence of the required amount of HCl to produce 1.29 g of an organic salt (quantitatively).
(Use Molar masses (in g mol^–1) of H, C, N, O, Cl and Sn as 1, 12, 14, 16, 35 and 119, respectively).

At 298 K, the limiting molar conductivity of a weak monobasic acid is 4 × 10² S cm² mol^–1. At 298 K, for an aqueous solution of the acid, the degree of dissociation is a and the molar conductivity is y × 10² S cm² mol^–1. At 298 K, upon 20 times dilution with water, the molar conductivity of the solution becomes 3y × 10² S cm² mol^–1.

For the following reaction $2 X+Y \xrightarrow{k} P$ the rate of reaction is $\frac{d[P]}{d t}=k[X]$ Two moles of $X$ are mixed with one mole of $Y$ to make $10\, L$ of solution At $50 \,s$, $05$ mole of $Y$ is left in the reaction mixture The correct statement(s) about the reaction is(are) (Use : $\ln\,2 = 0693)$

The boiling point of water in a $0.1$ molal silver nitrate solution (solution $A$ ) is $x ^{\circ} C$. To this solution $A$, an equal volume of $0.1$ molal aqueous barium chloride solution is added to make a new solution $B$. The difference in the boiling points of water in the two solutions $A$ and $B$ is $y \times 10^{-2}{ }^{\circ} C$
(Assume: Densities of the solutions $A$ and $B$ are the same as that of water and the soluble salts dissociate completely
Use: Molal elevation constant (Ebullioscopic Constant), $K _{ b }=0.5 \,K \,kg\, mol ^{-1}$; Boiling point of pure water as $100^{\circ} C$)

For the reaction, $X (s) \rightleftharpoons Y (s)+ Z (g)$, the plot of $\ln \frac{p_{ Z }}{p^{0}}$ versus $\frac{10^{4}}{T}$ is given below (in solid line), where $p_{ z }$ is the pressure (in bar) of the gas $Z$ at temperature $T$ and $p^0=1$ bar

 (Given, $\frac{ d (\ln K)}{ d \left(\frac{1}{T}\right)}=-\frac{\Delta H^{0}}{R}$, where the equilibrium constant, $K=\frac{p_{z}}{p^{0}}$ and the gas constant, $R=8314 \,J \,K ^{-1} mol ^{-1}$ )

For the following reaction scheme, percentage yields are given along the arrow: 

$X\, g$ and $y \,g$ are mass of $R$ and $U$, respectively. (Use : Molar mass (in $g \,mol^{-1})$ of $H, C$ and $O$ as $1, 12$ and $16$, respectively)

Newman projections P, Q, R and S are shown below:

 Which one of the following options represents identical molecules?

Choose the correct statement(s) among the following:

If the distribution of molecular speeds of a gas is as per the figure shown below, then the ratio of the most probable, the average, and the root mean square speeds, respectively, is

In thermodynamics, the $P-V$ work done is given by
$w=-\int d V P_{ ext }$
For a system undergoing a particular process, the work done is,
$w=-\int d V\left(\frac{R T}{V-b}-\frac{a}{V^{2}}\right)$
This equation is applicable to a