List of top Questions asked in JEE Main

Identify the product formed (A and E)

In the cumene to phenol preparation in presence of air, the intermediate is

Some reactions of $NO _2$ relevant to photochemical smog formation are

photochemical smog formation

Identify $A , B , X$ and $Y$

Incorrect statement for the use of indicators in acid-base titration is :

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of the hydrolysis increases
Reason R: $\,I ^{-}$is a good nucleophile as well as a good leaving group
In the light of the above statements, choose the correct answer from the options given below

Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : EM waves used for optical communication have longer wavelengths than that of microwave, employed in Radar technology.
Reason R : Infrared EM waves are more energetic than microwaves, (used in Radar)
In the light of given statements, choose the correct answer from the options given below:

Let f (x) = $\frac{x}{ (1+x ^n )^{\frac{1}{n} }}$, x∈R-{-1}, n∈N. n>2.
If fⁿ(x) = (fofof____upto n times) (x), then $lim ∫^1_ {n→∞ 0} x^{n-2}$( fⁿ(x))dx is equal to ___.

In an n-p-n common emitter (CE) transistor the collector current changes from 5 m A to 16 mA for the change in base current from 100 μ A and 200 μA , respectively. The current gain of transistor is Options 1. 110 2. 0.9 3. 210 4. 9

Which one of the following sets of ions represents a collection of isoelectronic species ?
(Given : Atomic Number : $F : 9, Cl : 17, Na =11, Mg =12, Al =13, K =19, Ca =20, Sc =21$)

Arrange the following in decreasing acidicstrength

The structures of major products A , B and C in the following reaction are sequence

For electron gain enthalpies of the elements denoted as$\Delta_{ eg } H$, the incorrect option is :

$CH_3 - CH_2 - CN \xrightarrow[\text{Ether}]{CH_3MgBr} A \xrightarrow{H_3O^+} B \xrightarrow[HCl]{Zn - Hg} C$ The correct structure of $C$ is

In a reaction,

reagents ' X ' and ' Y ' respectively are :

Given below are two statements :

Statement I : Sulphanilic acid gives esterification test for carboxyl group

Statement II : Sulphanilic acid gives red colour in Lassigne's test for extra element detection In the light of the above statements, choose the most appropriate answer from the options given below :

Match List I with List II :

List-I Polymer		List-II used for items
A	Nylon 6,6	I	Buckets
B	Low density polythene	II	Non-stick utensils
C	High density polythene	III	Bristles of brushes
D	Teflon	IV	Toys

An organic compound 'A' with emperical formula $C _6 H _6 O$ gives sooty flame on burning Its reaction with bromine solution in low polarity solvent results in high yield of $B .B$ is

Choose the correct set of reagents for the following conversion trans $\left( Ph - CH = CH - CH _3\right) \rightarrow \operatorname{cis}\left( Ph - CH = CH - CH _3\right)$

Consider the following reaction

The correct statement for product $B$ is It is

$H _2 O _2$ acts as a reducing agent in

Match List I with List II

LIST I		LIST II
A	X_eF₄	I	See-saw
B	SF₄	II	Square planar
C	NH₄+	III	Bent T-shaped
D	BrF₃	IV	Tetrahedral

Choose the correct answer from the options given below :

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are

Glycosidic linkage between $C _1$ of $\alpha$-glucose and $C_2$ of $\beta$-fructose is found in

The correct order of melting points of dichlorobenzenes is

The correct increasing order of the ionic radii is