List of top Questions asked in JEE Main

For a system undergoing isothermal process, heat energy is supplied to the system. Choose the option showing correct statements
(a) Internal energy will increase
(b) Internal energy will decrease
(c) Work done by system is positive
(d) Work done by system is negative
(e) Internal energy remains constant
Two conducting solid spheres (A & B) are placed at a very large distance with charge densities and radii as shown:
Choose the option showing the correct relation between Poisson’s ratio (σ), Bulk modulus (B) and modulus of rigidity (G).
For the adsorption of hydrogen on platinum, the activation energy is 30 kJ mol-1 and for the adsorption of hydrogen on nickel, the activation energy is 41.4 kJ mol-1 . The logarithm of the ratio of the rates of chemisorption on equal areas of the metals at 300 K is ……… (Nearest integer) Given: ln 10 = 2. 3  R = 8.3 JK-1 mol-1
Consider the graph of Gibbs free energy G vs Extent of reaction. The number of statement/s from the following which are true with respect to points (a), (b) and (c) is…

A. Reaction is spontaneous at (a) and (b)  
B. Reaction is at equilibrium at point (b) and nonspontaneous at point (c)  
C. Reaction is spontaneous at (a) and nonspontaneous at (c)  
D. Reaction is non-spontaneous at (a) and (b)
The number of species from the following which have square pyramidal structure is___
\(PF_5, BrF^− _4 4 − , IF_5\) ; \(BrF_5, XeOF_4, ICl ^−_ 4\)
the major product A and B from the the following reaction are
The major product formed in the following reaction is
Match List I with List II

List I 

Element detected

 

 List II 

Reagent used/ Product formed

ANitrogenINa2[Fe(CN)5 NO]
BSulphur IIAgNO3
CPhosphorousIIIFe4[Fe(CN)6]3
DHalogenIV(NH4)2 MoO4 

Choose the correct answer from the options given below:
 

Compound P is neutral. Q gives effervescence with NaHCO3
Compound P is neutral. Q gives effervescence with NaHCO3 while R reacts with Hinsbergs reagent to give solid soluble in NaOH. Compound P is
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R 
Assertion: Magnetic moment of [Fe(H2O)6]3+ is 5.92 BM and that of [Fe(CN)6]3– is 1.73 BM 
Reason: Oxidation state of Fe in both the complexes is +3. 
In the light of the above statements, choose the correct answer from the options given below
The standard electrode potential of M+/M in aqueous solution does not depend on
Match the terms in Column-I with their description in Column-II:
Column-I Column-II
PN2O5 (i)N–N bond
QN2O(ii)N–O–N bond
RN2O4 (iii)N=N / N≡N bond
SNO2(iv)N=O bond
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Radius of H+ is 1.5 × 10–3 pm
Reason (R) : H+ cannot exist independently
In the light of the above statements, write the detailed answer:
The difference between electron gain enthalpies will be maximum between
For $z \in C$ if the minimum value of $(| z -3 \sqrt{2}|+| z - p \sqrt{2} i |)$ is $5 \sqrt{2}$, then a value of $p$ is ______
Oxidation state of Cr in chromyl chloride is:
The homoleptic and octahedral complex of Co2+ and H2O has___ set of orbitals. unpaired electron(s) in the t2g set of orbitals.
The total change in the oxidation state of manganese involved in the reaction of KMnO4 and potassium iodide in the acidic medium is______
20 mL of 0.5 M NaCl is required to coagulate 200 mL of As2S3 solution in 2 hours. The coagulating value of NaCl is____
For a reversible reaction A ⇌ B, the ΔHforward reaction = 20 kJ mol-1. The activation energy of the uncatalysed forward reaction is 300 kJ mol-1. When the reaction is catalysed keeping the reactant concentration same, the rate of the catalysed forward reaction at 27°C is found to be same as that of the uncatalysed reaction at 327°C. The activation energy of the cataysed backward reactoion is ____ kJ mol-1.
Lowering of vapour pressure of 30% of aqueous solution of glucose. (in mmHg) 
Given: PH2O = 760 mm of Hg
30.4 kJ is required to melt one mole of sodium chloride. The entropy change during melting is 28.4 JK-1 mol-1 . atm The melting point of sodium chloride Calculate is ___ K(Nearest Integer).
The volume (in mL) of 0.1 M AgNO3 required for complete precipitation of chloride ions present in 20 mL of 0.01 M solution of [Cr(H2O)5CI]Cl2 as silver chloride is___
Which of the following statement is correct for paper chromatography?