List of top Questions asked in WBJEE

Increasing order of the nucleophilic substitution of following compounds is

Which of the following hydrocarbons reacts easily with MeMgBr to give methane? 

Kjeldahl's method cannot be used for the estimation of nitrogen in which compound? 

The major product (F) in the following reaction is 

In the following reaction, the major product (H) is

An optically active alkene having molecular formula C$_8$H$_{16$ gives acetone as one of the products on ozonolysis. The structure of the alkene is} 

Compound given below will produce effervescence when mixed with aqueous sodium bicarbonate solution 

Consider the gas phase dissociation, PCl$_5$(g) $\rightleftharpoons$ PCl$_3$(g) + Cl$_2$(g) with equilibrium constant $K_p$ at a particular temperature and pressure $P$. The degree of dissociation ($\alpha$) for PCl$_5$(g) is
An egg takes 4.0 minutes to boil at sea level where boiling point of water is $T_1$ K, whereas it takes 8.0 minutes to boil on a mountain top where boiling point of water is $T_2$ K. The activation energy for the reaction that takes place during boiling of egg is
$^{10_{5}$B + $^{4}_{2}$He $\rightarrow$ X + $^{1}_{0}$n. In the above nuclear reaction, X will be}
As per the following equation, 0.217 g of HgO (molecular mass = 217 g mol$^{-1}$) reacts with excess iodide. On titration of the resulting solution, how many mL of 0.01 M HCl is required to reach the equivalence point? \[ \text{HgO} + 4\text{I}^- + \text{H}_2\text{O} \rightarrow \text{HgI}_4^{2-} + 2\text{OH}^- \]
The bond order of HeH$^+$ is
360 cm$^3$ of a hydrocarbon diffuses in 30 minutes, while under the same conditions 360 cm$^3$ of SO$_2$ gas diffuses in one hour. The molecular formula of the hydrocarbon is
For a chemical reaction, half-life period ($t_{1/2}$) is 10 minutes. How much reactant will be left after 20 minutes if one starts with 100 moles of reactant and the order of the reaction be (i) zero, (ii) one and (iii) two?
How many oxygen atoms are present in 0.36 g of a drop of water at STP?
The coagulating power of electrolytes having ions Na$^+$, Al$^{3+$ and Ba$^{2+}$ for As$_2$S$_3$ sol increases in the order}
How many electrons are needed to reduce N$_2$ to NH$_3$?
The number of lone pair of electrons and the hybridization of Xenon (Xe) in XeOF$_2$ are
Increasing order of solubility of AgCl in (i) H$_2$O, (ii) 1M NaCl (aq.), (iii) 1M CaCl$_2$ (aq.), and (iv) 1M NaNO$_3$ (aq.) solution
The common stable oxidation states of Eu and Gd are respectively
Which of the following oxides is paramagnetic?
What is the four-electron reduced form of O$_2$?
Which of the following hydrogen bonds is likely to be the weakest?
Adiabatic free expansion of ideal gas must be
If three elements A, B, C crystallise in a cubic lattice with B at cube centres, C at edge centres and A at corners, the formula of the compound is