List of top Chemistry Questions asked in JEE Main

Manganese (VI) has ability to disproportionate in acidic solution. The difference in oxidation states of two ions it forms in acidic solution is _____.

In which of the following pairs, electron gain enthalpies of constituent elements are nearly the same or identical ?

(A) $Rb$ and $Cs$

(B) $Na$ and $K$

(C) $Ar$ and $Kr$

(D) $I $ and $At$

Choose the correct answer from the options given below :

While estimating the nitrogen present in an organic compound by Kjeldahl’s method, the ammonia evolved from 0.25 g of the compound neutralized 2.5 mL of 2 M H₂SO₄. The percentage of nitrogen present in organic compound is ________

Among the following the number of curves not in accordance with Freundlich adsorption isotherm is____.

Among the following the number of state variables is____.

For a reaction, given below is the graph of ln k vs 1/T. The activation energy for the reaction is equal to____ $cal mol^{–1}$. (Nearest integer)

(Given: $R = 2 cal K^{-1} mol^{-1}$)

Graph In k vs T

A sample of 0.125 g of an organic compound when analysed by Duma’s method yields 22.78 mL of nitrogen gas collected over KOH solution at 280 K and 759 mm Hg. The percentage of nitrogen in the given organic compound is____.(Nearest integer)

Given : 1. The vapour pressure of water of 280 K is 14.2 mm Hg.

2. R = 0.082 L atm K^–1 mol^–1

Which of the following relation is not correct?

Which of the following sets of quantum numbers is not allowed?

Which of the reaction is suitable for concentrating ore by leaching process?

Which of the following statement is incorrect?

What is the major product of the following reaction?

On complete combustion of 0.492 g of an organic compound containing C, H and O, 0.7938 g of CO₂ and 0.4428 g of H₂O was produced. The % composition of oxygen in the compound is _______.

The major product of the following reaction is

The number of interhalogens from the following having square pyramidal structure is :CIF3, IF7, BrF5, BrF3, I2CI6, IF5, CIF, CIF5

For the given first order reaction A → B, the half-life of the reaction is 0.3010 min. The ratio of the initial concentration of reactant to the concentration of reactant at time 2.0 min will be equal to ______. (Nearest integer)

Ka for butyric acid (C₃H₇COOH) is 2 × 10^–5. The pH of 0.2 M solution of butyric acid is ______× 10^–1. (Nearest integer) (Given log2 = 0.30)

On reaction with stronger oxidizing agent like KIO₄, hydrogen peroxide oxidizes with the evolution of O₂. The oxidation number of I in KIO₄ changes to____.

Some drugs bind to a site other than the active site of an enzyme. This site is known as

The compound(s) that is(are) removed as slag during the extraction of copper is
(A) CaO
(B) FeO
(C) Al₂O₃
(D) ZnO
(E) NiO
Choose the correct answer from the options given below :

Match List - I with List - II
List I List II
A $N _2( g )+3 H _2( g ) \rightarrow 2 NH _3( g )$ I $Cu$
B $CO ( g )+3 H _2( g ) \rightarrow CH _4( g )+ H _2 O ( g )$ II $Cu / ZnO - Cr _2 O _3$
C $CO ( g )+ H _2( g ) \rightarrow HCHO ( g )$ III $Fe _x O _y+ K _2 O + Al _2 O _3$
D $CO ( g )+2 H _2$ (g) $\rightarrow CH _3 OH ( g )$ IV $Ni$
Choose the correct answer from the optionsgiven below :

Match List - I with List - II

List-I (Processes/Reactions)		List-II (Catalyst)
A	$2 SO _2( g )+ O _2( g ) \rightarrow 2 SO _3( g )$	I	$Fe ( s )$
B	$4 NH _3( g )+5 O _2( g ) \rightarrow$$4 NO ( g )+6 H _2 O ( g )$	II	$Pt ( s )- Rh ( s )$
C	$N _2( g )+3 H _2( g ) \rightarrow 2 NH _3( g )$	III	$V _2 O _5$
D	Vegetable oil $(l)+ H _2 \rightarrow$Vegetable ghee(s	IV	$Ni ( s )$

Choose the correct answer from the options given below:

Given two statements below:
Statement I: In $Cl _2$ molecule the covalent radius is double of the atomic radius of chlorine.
Statement II: Radius of anionic species is always greater than their parent atomic radius Choose the most appropriate answer from options given below:

Match List-I with List-II, match the gas evolved during each reaction:

List-I		List-II
(A)	$\left( NH _4\right)_2 Cr _2 O _7 \xrightarrow{\Delta}$	(I)	$H _2$
(B)	$KMnO _4+ HCl \rightarrow$	(II)	$N _2$
(C)	$Al + NaOH + H _2 O \rightarrow$	(III)	$O _2$
(D)	$NaNO _3 \xrightarrow{\Delta}$	(IV)	$Cl _2$

Choose the correct answer from the options given below: