List of top Chemistry Questions asked in JEE Main

Find correct order of covalent character (A) \(KF < KI\) (B) \(CuCl > NaCl\) (C) \(LiF > KF\)

Number of unpaired electron in highest occupied molecular orbital of following species is :\(N_2, N ^+_ 2 , O_2, O^+_ 2 \) ? 

Statement-I: Noradrenaline is one of the neurotransmitter. 

Statement-II: Low level of noradrenaline is not cause of depression in humans.

In light of the above statements, choose the correct answer from the options given below

The starting material for convenient preparation of deuterated hydrogen peroxide \(\left(D_2 O _2\right)\) in laboratory is :

\([Co(NH_3)_6]^{3+} \text{is} \) ________\(\text{hybridised and}\)________
How many reactions are non-spontaneous at 300 K. For independent reaction ΔH & ΔS values are given.
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

Match List I with List II:

LIST I (Type) LIST II (Name)
(P) Antifertility drugs(A) Norethindrone 
(Q) Antihistamines(B) Seldane
(R) Tranquilizers(C) Meprobamate
(S) Antibiotics(D) Penicillin

Choose the correct answer from the options given below:

Which of the following complex will show largest splitting of $d$-orbitals?

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R 
Assertion (A) : Benzene is more stable than hypothetical cyclohexatriene 
Reason (R) : The delocalised π-electrons cloud is attracted more strongly by the nuclei of the carbon atoms than the electron cloud localised between two carbon atoms.
In the light of the above statements, choose the correct answer from the options given below

Given below are two statements:
Statement-I: Pure Aniline and other arylamines are usually colourless.
Statement-II: Arylamines get coloured on storage due to atmospheric reduction
In the light of the above statements, choose the most appropriate answer from the options given below:

\(H_2O_2\) behave like reducing agent in which of the following reactions:

S1: Be+2 has higher SRP than other alkaline earth metals.
S2: Be+2 has higher hydration energy and greater △aH (atomisation enthalpy) than other alkaline earth metals.

Match the following:
Column-IColumn-II
(A) Zone refining(P) pig iron
(B) Electrolysis(Q) Al
(C) Reverberatory furnace(R) Si
(D) Blast furnace(S) Cu
Freezing point of solution is less than that of pure solvent, which of the following statements are correct ? 
(A) Vapour pressure of solution is less than that of pure solvent 
(B) Vapour pressure of solution is greater than that of pure solvent 
(C) Only solvent molecules will freeze 
(D) Only solute molecules will freeze

Graph of X-ray frequency (v)n v/s atomic number (Z) is linear. Find the value of n.

\(A(g) ⇋ 2B(g) + C(g)\)
For the given reaction, if the initial pressure is 450 mm Hg and the pressure at time t is 720 mm Hg at a constant temperature T and constant volume V. The fraction of A(g) decomposed under these conditions is \(x × 10^{–1}\). The value of x is _____ . (nearest integer)
In alkaline medium, the reduction of permanganate anion involves a gain of _____ electrons.
The electron in the \(n^{th}\) orbit of \(Li^{2+}\) is excited to \((n + 1)\) orbit using the radiation of energy \(1.47 × 10^{–1}J \) (as shown in the diagrarn). The value of n is ______ .
Given: \(R_H = 2.18 × 10^{–18} J\).
The number of incorrect statement/s from the following is ____ .
A. The successive half lives of zero order reactions decreases with time.
B. A substance appearing as reactant in the chemical equation may not affect the rate of reaction.
C. Order and molecularity of a chemical reaction can be a fractional number.
D. The rate constant units of zero and second order reaction are mol L–1s–1 and mol–1 Ls–1 respectively.
The number of endothermic process/es from the following is _____ .
A. \(I_2 (g) → 2I (g)\)
B. \(HCl (g) → H(g) + Cl (g)\)
C. \(H_2O(l) → H_2O (g)\)
D. \(C(s) + O_2 (g) → CO_2 (g)\)
E. Dissolution of ammonium chloride in water.
The difference in the oxidation state of \(Xe\) between the oxidised product of \(Xe\) formed on complete hydrolysis of \(XeF_4\) and \(XeF_4\) is _____ .
An aqueous solution of volume 300 cm3 contains 0.63 g of protein. The osmotic pressure of the solution
at 300 K is 1.29 mbar. The molar mass of the protein is ____ g mol–1.
Given: R = 0.083 L bar K–1 mol–1
The specific conductance of 0.0025 M acetic acid is \(5 × 10^{–5} S\ cm^{–1}\) at a certain temperature. The dissociation constant of acetic acid is ___________ \(× 10^{–7}.\) (Nearest integer) Consider limiting molar conductivity of \(CH_3COOH\) as \(400\  S cm^2 mol^{–1}\).
The number of molecules from the following which contain only two lone pair of electrons is _____ .
\(H_2O, N_2, CO, XeF_4, NH_3, NO, CO_2, F_2\)