List of top Chemistry Questions asked in JEE Main

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 $N_A=6.02×10^{23}$)

The denticity of the ligand present in the Fehling's reagent is ____ .

Total number of acidic oxides among $N_2O_3,NO_2, N_2O,Cl_2O_7,SO_2,CO,CaO,Na_2O$ and NO is ____ .

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)

Match List I and List II

List II	List II
A. van't Hoff factor, i	I. Cryoscopic constant
B. $k_f$	II. Isotonic solutions
C. Solution with same  with same osmotic pressure	III.  Normal molar mass /Abnormal molar mass
D. Azeotropes	IV. Solutions with same composition of  vapour above it

Choose the correct answer from the options given below :

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:

Given below are two statements: 
Statement I: Nickel is being used as the catalyst for producing syn gas and edible fats. 
Statement II : Silicon forms both electron rich and electron deficient hydrides. 
In the light of the above statements, choose the most appropriate answer from the options given below:

Following tetrapeptide can be represented as

(F, L, D, Y, I, Q, P are one letter codes for amino acids)

Reaction of propanamide with $Br_2/KOH(aq)$ produces :

According to MO theory the bond orders for \(O_2^{2−},CO\,\, \text {and} \,\,NO^+\) respectively, are

Find out the major products from the following reaction sequence.

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?

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

A doctor prescribed the drug Equanil to a patient. The patient was likely to have symptoms of which disease?

An indicator ' X ' is used for studying the effect of variation in concentration of iodide : on the rate of reaction of iodide ion with $H_2O_2 $ at room temp. The indicator ' X ' forms blue colored complex with compound ' A ' present in the solution. The indicator ' X ' and compound 'A' respectively are

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 :

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.

Match List I and List II

List II	List II
A. Osmosis	I. Solvent molecules pass through semi permeable membrane towards solvent side.
B. Reverse osmosis	II. Movement of charged colloidal particles under the influence of applied electric  potential towards  oppositely charged electrodes.
C. Electro osmosis	III. Solvent molecules pass through semi permeable  membrane towards solution side.
D. Electrophoresis	IV. Dispersion medium moves in an electric field.

Choose the correct answer from the options given below :

Correct order of spin only magnetic moment of the following complex ions is:
(Given At.no. Fe: 26, Co:27)

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): Gypsum is used for making fireproof wall boards
Reason (R): Gypsum is unstable at high temperatures
In the light of the above statements, choose the correct answer from the options given below :

See the following chemical reaction: \[ \text{Cr}_2\text{O}_7^{2-} + \text{XH}^+ + \text{6Fe}^{2+} \rightarrow \text{YCr}^{3+} + \text{6Fe}^{3+} + \text{ZH}_2\text{O}. \] The sum of \(X\), \(Y\), and \(Z\) is _____.

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

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:

Maximum number of electrons that can be accommodated in shell with $n=4$ are:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason $R$ 
Assertion A : Antihistamines do not affect the secretion of acid in stomach 
Reason R : Antiallergic and antacid drugs work on different receptors 
In the light of the above statements, choose the correct answer from the options given below: