List of top Chemistry Questions asked in WBJEE

Acid catalysed hydrolysis of ethyl acetate follows a pseudo-first order kinetics with respect to ester. If the reaction is carried out with large excess of ester, the order with respect to ester will be

For isothermal expansion of an ideal gas, the correct combination of the thermodynamic parameters will be

In diborane, the number of electrons that account for bonding in the bridges is

In borax the number of $B-O-B$ links and $B-OH$ bonds present are, respectively,

$58.4\, gm$ of $NaCl$ and $180\,gm$ of glucose were separately dissolved in $1000 \,mL$ of water. Identify the correct statement regarding the elevation of boiling point ($b.pt$) of the resulting solutions.

If the first ionization energy of $H$ atom is $13.6\, eV$, then the $2^{nd}$ ionization energy of He atom is

Which of the following solutions is an example of negative deviation from Raoult�s law?

$20\, mL\, 0.1( N )$ acetic acid is mixed with $10\, mL$ $0.1( N )$ solution of $NaOH$. The $pH$ of the resulting solution is $\left( p K_{a}\right.$ of acetic acid is $4.74$ )

The state of hybridization of the central atom and the number of lone pairs over the central atom in $POCl_{3}$ are

Under identical conditions, the $S_N1$ reaction will occur most efficiently with

Which one of the following is wrong about molecularity of a reaction?

The weight of oxalic acid that will be required to prepare a $1000\, mL$ $\left(\frac{N}{20}\right)$ solution is

Equal weights of $CH_{4}$ and $H_{2}$ are mixed in an empty container at $25^\circ C$. The fraction of the total pressure exerted by $H_{2}$ is

In a reversible chemical reaction at equilibrium, if the concentration of any one of the reactants is doubled, then the equilibrium constant will

Which of the following does not represent the mathematical expression for the Heisenberg uncertainty principle?

An equimolar mixture of toluene and chlorobenzene is treated with a mixture of conc. $H_{2} SO_{2}$ and conc. $HNO_{3}.$ Indicate the correct statement from the following.

The $sp^3d^2$ hybridization of central atom of a molecule would lead to

The standard reduction potential $E^o$ for half reations are $Zn = Zn^{2+} + 2e^- ;\,\,E^o = +0.76 V$ $Fe = Fe^{2+} + 2e^-;\,\, E^o = + 0.41 V$ The EMF of hte cell reaction $Fe^{2+} + Zn = Zn^{2+} + Fe$ is

The pH of an aqueous solution of $CH_3COONa$ of concentrated $C(M)$ is given by

$2\,gm$ of metal carbonate is neutralized completely by $100 \,mL$ of $0.1 \,(N) \,HCl$. The equivalent weight of metal carbonate is

The normality of $30$ volume $H_2O_2$ is

$20\, mL$ of $0.2\, M \,NaOH$ is added to $50\, mL$ of $0.2\, M$ acetic acid. The pH of this solution after mixing is $(Ka = 1.8 \times 10^{-5})$

If the equilibrium constants of the following equilibria ${SO_{2(g)} +\frac{1}{2}O2 <=> SO3$ $ and\, 2SO_{3(g)} <=> 2SO_{2(g)} +O_{2(g)}}$ are given by $K_1$ and $K_2$ respectively, which of the following relations is correct

Two soap bubbles of radii $x$ and $y$ coalesce to constitute a bubble of radius $z$. Then $z$ is equal to

Two aromatic compounds having formula $C_7H_8O$ which are easily identifiable by $FeCl_3$ solution test (violet colouration) are