List of top Questions asked in WBJEE

Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute NaOH solution and x kcal and y kcal of heat are liberated respectively.  Which of the following is true?

Hybridisation of central atom in NF3 is 

For the Paschen series the values of n1 and n2 in the expression $$\mathrm{\Delta }E=Rhc(\frac{1}{n_1^2}-\frac{1}{n_2^2})$$

Under which of the following condition is the relation valid $\mathrm{\Delta }H=\mathrm{\Delta }E+P\mathrm{\Delta }V$ for a closed system?

The general solution of the differential equation $\frac{d^{2}y}{d{x}^2}+8\frac{dy}{dx}+16y=0$ is

The number of solutions of log2(x – 1) = 2 log2(x – 3) is

$\sum _{r=0}^{m}n+r{c}_r$ is equal to

The locus of the centre of a circle which passes through two variable points (a, 0), (–a, 0) is 

At temperature 300 K for reaction  C2H4(g) + 3O2(g)→ 2CO2(g) + 2H2O(g); ΔH = −336.2 kcal.  The approximate value of ΔU  at 300 K for the same reaction (R = 2 cal degree^{− 1} mol^{− 1}) will be-

A compound is formed by substitution of two chlorine for two hydrogens in propane. The number of possible isomeric compounds is 

If nt number of radioatoms are present at time t, the following expression will be a constant : 

Of the following acids the one which has the capability to form complex compound and also possesses oxidizing and reducing properties is:

Atoms in a P4 molecule of white phosphorus are arranged regularly in the following way : 

Ethelene can be separated from acetylene by passing the mixture through : 

Out of the 20 amino acids, only two of them contain sulfur. Those two amino acids are:

The derivative of f(tan x) w.r.t. g(sec x) at x = π/4 where f`(1) = 2 and g`(√2) =4, is

$\mathrm{f}\mathrm{A}+\mathrm{B}+\mathrm{C}=,$ then $\tan \left(\frac{\mathrm{A}}{2}\right)\tan \left(\frac{\mathrm{B}}{2}\right)+\tan \left(\frac{\mathrm{B}}{2}\right)\tan \left(\frac{\mathrm{C}}{2}\right)+\tan \left(\frac{\mathrm{C}}{2}\right)\tan \left(\frac{\mathrm{A}}{2}\right)$ is equal to

If $y=2x^3-2x^2+3x-5$, then for $x=2$ and $\mathrm{\Delta }x=0.1$ value of $\mathrm{\Delta }y$ is:

The approximate value of 5√33 correct to 4 decimal places is 

The general solution of the differential equation ${\log }_e\left(\frac{dy}{dx}\right)=x+y$ is

The number of solutions of  2sin x + cos x = 3 is 

If A and B are coefficients of xⁿ in the expansions of (1+ x)2ⁿ and (1+x)^{2n – 1} respectively, then A/B is equal to 

If it is assumed that ${}_{\mathrm{\infty }}^{235}U$ decays only by emitting a and $\beta$ particles, the possible product of the decay is:

The reaction that takes place when Cl2 gas is passed through conc. NaOH solution is :