List of top Chemistry Questions

In the following sequence of reactions the P is: 

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

 

When 10 mL of an aqueous solution of \(KMnO_4\) was titrated in acidic medium, equal volume of 0.1 M of an aqueous solution of ferrous sulphate was required for complete discharge of colour. The strength of \(KMnO_4\) in grams per litre is _________ \(\times 10^{-2}\). (Nearest integer)
[ Atomic mass of \(K = 39, Mn = 55, O = 16\) ]
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:
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Synthesis of ethyl phenyl ether may be achieved by Williamson synthesis.
Reason (R): Reaction of bromobenzene with sodium ethoxide yields ethyl phenyl ether.
In the light of the above statements, choose the most appropriate answer from the options given below :
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:
In polythionic acid, H\(_2\)S\(_x\)O\(_6\) (x = 3 to 5) the oxidation state(s) of sulphur is/are :
In which one of the following molecules strongest back donation of an electron pair from halide to boron is expected?
Which refining process is generally used in the purification of low melting metals ?
Deuterium resembles hydrogen in properties but :
The number of water molecules in gypsum, dead burnt plaster and plaster of Paris, respectively are :
The unit of the van der Waals gas equation parameter 'a' in \(\left(P + \frac{an^2}{V^2}\right)(V - nb) = nRT\) is:

The major product formed in the following reaction is : 

The correct options for the products A and B of the following reactions are : 

Among the following compounds I-IV, which one forms a yellow precipitate on reacting sequentially with (i) NaOH (ii) dil. $HNO_3$ (iii) $AgNO_3$? 

The major product formed in the following reaction is : 

Excess of isobutane on reaction with $Br_2$ in presence of light at $125^\circ C$ gives which one of the following, as the major product ? 

The total number of negative charge in the tetrapeptide, Gly-Glu-Asp-Tyr, at pH 12.5 will be _________. (Integer answer)
The number of 4f electrons in the ground state electronic configuration of \(Gd^{2+}\) is _________. [Atomic number of Gd = 64] (Integer answer)
The \(OH^-\) concentration in a mixture of 5.0 mL of 0.0504 M \(NH_4Cl\) and 2 mL of 0.0210 M \(NH_3\) solution is \(x \times 10^{-6}\) M. The value of \(x\) is _________. (Nearest integer)
[Given \(K_w = 1 \times 10^{-14}\) and \(K_b = 1.8 \times 10^{-5}\)]
The polymer formed on heating Novolac with formaldehyde is :