List of top Chemistry Questions asked in JEE Main

How many of the following metal ions have similar value of spin only magnetic moment in gaseous state? (Given: Atomic number: $V, 23; Cr, 24; Fe, 26; Ni, 28$) $V ^{3+} \cdot Ci ^{3+} \cdot Fe ^{2+} \cdot Ni ^{3+}$

For $OF _2$ molecule consider the following : A Number of lone pairs on oxygen is 2 B FOF angle is less than $1045^{\circ}$ C Oxidation state of $O$ is $-2$ D Molecule is bent ' $V$ ' shaped E Molecular geometry is linear correct options are:

If the formula of borax is \(Na_2B_4Ox(OH)y.zH_2O\) , Find the value of x + y + z. 

A $300\, mL$ bottle of soft drink has $0.2 \,M\, CO _2$ dissolved in it Assuming $CO _2$ behaves as an ideal gas, the volume of the dissolved $CO _2$ at STP is ______$mL$ (Nearest integer) Given : At STP, molar volume of an ideal gas is $227\, L \,mol ^{-1}$

Number of moles of $AgCl$ formed in the following reaction is

$P t(s)\left|II_2( g )(1 bar )\right| II^{+}(a q)(1 M)|| M^{3+}(a q), M^{+}(a q) \mid P t(s)$ The $E _{\text {cell }}$ for the given cell is $01115 V$ at $298 K$ when $\frac{\left[M^{+}(a q)\right]}{\left[M^{3+}(a q)\right]}=10^{\circ}$ The value of $a$ is _____ Given : $E ^\theta M ^{3+} M ^{+}=02 V$ $\frac{2303 R T}{F}=0059 V$

On heating, $LiNO_3$ gives how many compounds among the following?
$Li_2O,N_2,O_2,LiNO_2,NO_2 $

For conversion of compound \(A→B\), the rate constant of the reaction was found to be $4.6×10^{−5} L mol^{−1} s^{−1}$. The order of the reaction is _____ .

Given below are two statements, one is labelled as Assertion $A$ and the other is labelled as Reason $R$
Assertion A: Carbon forms two important oxides - $CO$ and $CO _2 .CO$ is neutral whereas $CO _2$ is acidic in nature
Reason R : $CO _2$ can combine with water in a limited way to form carbonic acid, while $CO$ is sparingly soluble in water
In the light of the above statements, choose the most appropriate answer from the options given below

$KMnO _4$ oxidises $I ^{-}$in acidic and neutral/faintly alkaline solution, respectively, to

Given below are two statements:
Statement I : In froth floatation method a rotating paddle agitates the mixture to drive air out of it.
Statement II : Iron pyrites are generally avoided for extraction of iron due to environmental reasons.
In the light of the above statements, choose the correct answer from the options given below:

Given below are two statements:
Statement I : During Electrolytic refining, the pure metal is made to act as anode and its impure metallic form is used as cathode
Statement II : During the Hall-Heroult electrolysis process, purified $Al _2 O _3$ is mixed with $Na _3 AlF _6$ to lower the melting point of the mixture
In the light of the above statements, choose the most appropriate answer from the options given below:

When 0.01 mol of an organic compound containing 60% carbon was burnt completely, 4.4 g of $CO_2$ was produced. The molar mass of compound is _______ $gmol^{−1}$. (Nearest integer).

What is the correct order of acidity of the protons marked A-D in the given compounds?

When a hydrocarbon A undergoes complete combustion it requires 11 equivalents of oxygen and produces 4 equivalents of water. What is the molecular formula of $A$?

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: In an Ellingham diagram, the oxidation of carbon to carbon monoxide shows a negative slope with respect to temperature
Reason R: CO tends to get decomposed at higher temperature
In the light of the above statements, choose the correct answer from the options given below

The one giving maximum number of isomeric alkenes on dehydrohalogenation reaction is
(excluding rearrangement)

Match List I and List II

List II	List II
A. Elastomeric polymer	I. Urea formaldehyde resin
B. Fibre Polymer	II. Polystyrene
C. Thermosetting Polymer	III. Polyester
D. Thermoplastic Polymer	IV. Neoprene

Choose the correct answer from the options given below :

Find out the major products from the following reaction sequence.

The set of correct statements is :
(i) Manganese exhibits +7 oxidation state in its oxide. 
(ii) Ruthenium and Osmium exhibit +8 oxidation in their oxides. 
(iii) Sc shows +4 oxidation state which is oxidizing in nature. 
(iv) Cr shows oxidising nature in +6 oxidation state.

When a hydrocarbon A undergoes combustion in the presence of air, it requirs 9.5 equivalents of oxygen and produces 3 equivalents of water. What is the molecular formula of A?

At \(298\ K\)
\(N_2( g)+3H_2( g)⇌2NH_3( g),K_1=4×10^5\)
\(N_2( g)+O_2( g)⇌2NO(g),K_2=1.6×10^{12}\)
\(H_2( g)+1 2O_2( g)⇌H_2O(g),K_3=1.0×10^{−13}\)
Based on above equilibria, the equilibrium constant of the reaction, 
\(2NH_3( g)\)+\(\frac5 {2}\) \(O_2( g)⇌2NO(g)+3H_2O(g)\) is _______ \(×10^{−33 }\). (Nearest integer)

A metal 𝑀 forms hexagonal close-packed structure. The total number of voids in 0.02 mol of it is _______ $×10^{21}$. (Nearest integer).
( Given $N_A=6.02×10^{23}$)

Which of the following relations are correct? 
(A) \(ΔU=q+pΔV\)
(B) \(ΔG=ΔH−TΔS\)
(C) \(ΔS=\frac{𝑞_{𝑟𝑒𝑣}}{𝑇}\)
(D) \(ΔH=ΔU−ΔnRT\)
Choose the most appropriate answer from the options given below: