List of top Questions asked in WBJEE

The correct stability order of the following carbocations is : (I)H₂C⨁-CH=CH-CH₃, (II)⨁CH₂-CH=CH-BMe₂, (III)H₂C⨁-CH=CH-NMe₂, (IV)H₂C⨁-CH=CH-OMe

What is the edge length of the unit cell of a body-centred cubic crystal of an element whose atomic radius is 75 pm?

Arrange the following in order of increasing mass :
(i) 1 mole of N₂, (ii) 0.5 mole of O₃, (iii) \(3.011×10^{23}\) molecules of O₂, (iv) 0.5 gram atom of O₂

The average ordinate of y=sin x over [0,\(\pi\)] is

If a hyperbola passes through the point P(\(\sqrt{2},\sqrt{3}\)) and has foci at (±2,0), then the tangent to this hyperbola at P is

If 1,\(log_9\)(\(3^{1-x}+2\)).\(log_3\)(\(4.3^x-1\)) are in A.P. then \(x\) equals 

The IUPAC name of CH₃CH=C-CHO-CH₂-CH₃ is:

 
'G' in the above sequence of reaction is

The molecular shapes of SF₄,CF₄ and XeF₄ are

A solution containing 4g of polymer in a 4.0-litre solution at 27°C shows an osmotic pressure of 3.0×10^-4 atm. The molar mass of the polymer in g/mol is

(i)(ii)(iii)(iv)
The correct order of acidity of above compound is 

The correct option for the above reaction is 

Let f be a non-negative function defined on [\(0,\frac{\pi}{2}\)]. If \(\int_{0}^{x}(f'(t)-sin\,2t)dt=\int_{0}^{x}f(t)tan\,t\,dt\). \(f(0)=1\), then \(\int_{0}^{\frac{\pi}{2}}f(x)dx\) is

The value of \(\lim_{n\rightarrow\infty}[(\frac{1}{2.3}+\frac{1}{2^2.3})+(\frac{1}{2^2.3^2}+\frac{1}{2^3.3^2})+.....+(\frac{1}{2^n.3^n}+\frac{1}{2^{n+1}.3^n})]\)

If y=\(\frac{x}{log_e|cx|}\) is the solution of the differential equation \(\frac{dy}{dx}=\frac{y}{x}+\phi(\frac{x}{y})\), then \(\phi (\frac{x}{y})\) is given by 

Let f:[1,3]\(\rightarrow\)R be continuous and be derivable in (1,3) and f'(x)=[f(x)]²+4∀x∈(1,3). Then

In the extraction of genetic material (DNA), which enzyme is not used?

BrF₃ self ionizes as following

The species in which nitrogen atom is in a state of sp hybridisation is

Suppose a gaseous mixture of He,Ne,Ar and Kr is irradiated with photons of the frequency appropriate to ionize Ar,What ion(s) will be present in the mixture?

If in the case of a radio-isotope, the value of half-life(T_1/2) and decay constant(λ) are identical in magnitude, then their value should be

Na₂CO₃ is prepared by Solvay process but K₂CO₃ can not be prepared by the same because

The equivalent conductance of NaCl, HCl, and CH₃COONa at infinite dilution are 126.45, 426.16, and 91 ohm^-1cm²eq^-1 respectively at 25°C. The equivalent conductance of acetic acid(at infinite dilution) would be

The family of curves y=e^{asin x}, where a is an arbitrary constant, is represented by the differential equation