List of top Chemistry Questions asked in JEE Main

100 g of propane is completely reacted with 1000 g of oxygen. The mole fraction of carbon dioxide in the resulting mixture is \(x \times 10^{-2}\). The value of x is _________. (Nearest integer)
[Atomic weight : H=1.008; C=12.00; O=16.00]
When 5.1 g of solid NH\(_4\)HS is introduced into a two litre evacuated flask at 27\(^\circ\)C, 20% of the solid decomposes into gaseous ammonia and hydrogen sulphide. The K\(_p\) for the reaction at 27\(^\circ\)C is \(x \times 10^{-2}\). The value of x is _________. (Integer answer)
[Given R = 0.082 L atm K\(^{-1}\) mol\(^{-1}\)]
The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 mW and wavelength of 1000 nm, in 0.1 second is \(x \times 10^{13}\). The value of x is _________. (Nearest integer)
(h = 6.63 \(\times\) 10\(^{-34}\) Js, c=3.00 \(\times\) 10\(^8\) ms\(^{-1}\))
The addition of dilute NaOH to Cr\(^{3+}\) salt solution will give :
Given below are two statements:
Statement I : Ethyl pent-4-yn-oate on reaction with CH\(_3\)MgBr gives a 3\(^\circ\)-alcohol.
Statement II : In this reaction one mole of ethyl pent-4-yn-oate utilizes two moles of CH\(_3\)MgBr.
In the light of the above statements, choose the most appropriate answer from the options given below :
The major product (A) formed in the reaction given below is :
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Which one of the following tests used for the identification of functional groups in organic compounds does not use copper reagent ?
In stratosphere most of the ozone formation is assisted by :
Potassium permanganate on heating at 513 K gives a product which is :
Which one of the following is used to remove most of plutonium from spent nuclear fuel ?
Which one of the following is formed (mainly) when red phosphorus is heated in a sealed tube at 803 K ?
Lyophilic sols are more stable than lyophobic sols because,
The oxide that gives H\(_2\)O\(_2\) most readily on treatment with H\(_2\)O is :
Choose the correct statement from the following:
The correct order of ionic radii for the ions, P\(^{3-}\), S\(^{2-}\), Ca\(^{2+}\), K\(^{+}\), Cl\(^{-}\) is:

The correct statement about (A), (B), (C) and (D) is: 

The major product of the following reaction is: 

In the following sequence of reactions the P is: 

In the following sequence of reactions, the final product D is : 

 

In Carius method for estimation of halogens, 0.2 g of an organic compound gave 0.188 g of $AgBr$. The percentage of bromine in the compound is _________. (Nearest integer)
[Atomic mass : $Ag = 108, Br = 80$]
The number of \(f\) electrons in the ground state electronic configuration of Np (\(Z = 93\)) is _________. (Integer answer)
The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to \(\frac{h^2}{x m a_0^2}\). The value of \(10x\) is _________. (\(a_0\) is radius of Bohr's orbit)
(Nearest integer)
[ Given : \(\pi = 3.14\) ]
The nature of oxides V\(_2\)O\(_3\) and CrO is indexed as 'X' and 'Y' type respectively. The correct set of X and Y is:
The gas 'A' is having very low reactivity reaches to stratosphere. It is non-toxic and non-flammable but dissociated by UV-radiations in stratosphere. The intermediates formed initially from the gas 'A' are:
Tyndall effect is more effectively shown by: