List of top Chemistry Questions asked in JEE Main


The correct sequence of reagents for the above conversion of X to Y is :

Consider the general reaction given below at 400 K: xA(g) ⇌ yB(g). The values of K___p and K___c are studied under the same condition of temperature but variation in x and y.
(i) K___p = 85.87 and K___c = 2.586
(ii) K___p = 0.862 and K___c = 28.62.
The values of x and y in (i) and (ii) respectively are :
The statements that are incorrect about the nickel(II) complex of dimethylglyoxime are :
A. It is red in colour.
B. It has a high solubility in water at pH = 9.
C. The Ni ion has two unpaired d-electrons.
D. The N – Ni – N bond angle is almost close to 90°.
E. The complex contains four five-membered metallacycles (metal containing rings).
Choose the correct answer from the options given below :

Which one of the following graphs accurately represents the plot of partial pressure of CS₂ vs its mole fraction in a mixture of acetone and CS₂ at constant temperature?

Identify the molecule (X) with maximum number of lone pairs of electrons (obtained using Lewis dot structure) among HNO₃, H₂SO₄, NF₃, and O₃. Choose the correct bond angle made by the central atom of the molecule (X).
x mg of pure HCl was used to make an aqueous solution. 25.0 mL of 0.1 M Ba(OH)₂ solution is used when the HCl solution was titrated against it. The numerical value of x is_______ × 10⁻¹. (Nearest integer) Given: Molar mass of HCl and Ba(OH)₂ are 36.5 and 171.0 g mol⁻¹ respectively.}

Compound 'P' undergoes the following sequence of reactions : (i) NH₃ (ii) $\Delta$ $\rightarrow$ Q (i) KOH, Br₂ (ii) CHCl₃, KOH (alc), $\Delta$ $\rightarrow$ NC-CH₃. 'P' is : 

Which of the following statements regarding the energy of the stationary state is true in the following one-electron systems ?
The correct statements from the following are :
A. Ionic radii of trivalent cations of group 13 elements decreases down the group.
B. Electronegativity of group 13 elements decreases down the group.
C. Among the group 13 elements, Boron has highest first ionisation enthalpy.
D. The trichloride and triiodide of group 13 elements are covalent in nature.
Choose the correct answer from the options given below :

For the thermal decomposition of reactant AB(g), the following plot is constructed. 

The half life of the reaction is 'x' min.
x =_______} min. (Nearest integer)} 
 

Given, (A) n=5, m___l = -1; (B) n=3, l=2, m___l = -1, m___s = +1/2. The maximum number of electron(s) in an atom that can have the quantum numbers as given in (A) and (B) respectively are :
For the following gas phase equilibrium reaction at constant temperature, NH₃(g) = 1/2 N₂(g) + 3/2 H₂(g) if the total pressure is √3 atm and the pressure equilibrium constant (K___p) is 9 atm, then the degree of dissociation is given as (x × 10⁻²)⁻¹/². The value of x is_______ (nearest integer)}
Given below are two statements:
Statement I: [CoBr₄]²⁻ ion will absorb light of lower energy than [CoCl₄]²⁻ ion.
Statement II: In [CoBr₄]²⁻ ion, the energy separation between the two set of d-orbitals is more than [CoCl₄]²⁻ ion.
In the light of the above statements, choose the correct answer from the options given below :
The crystal field splitting energy of $[Co(oxalate)_3]^3-$ complex is 'n' times that of the $[Cr(oxalate)_3]^3-$ complex. Here 'n' is_______ (Assume $\Delta_0 > P$)}

Match List-I with List-II. 

Consider all the structural isomers with molecular formula C₃H₅Br are separately treated with KOH(aq) to give respective substitution products, without any rearrangement. The number of products which can exhibit optical isomerism from these is_______.
The correct trend in the first ionization enthalpies of the elements in the 3rd period of periodic table is :

From the given following (A to D) cyclic structures, those which will not react with Tollen's reagent are : 

Consider the following compounds. Arrange these compounds in a n increasing order of reactivity with nitrating mixture. The correct order is : 

Consider the following sequence of reactions:

4-nitrotoluene
Assuming that the reaction proceeds to completion, then 137 mg of 4-nitrotoluene will produce_______ mg of B. (Given molar mass in g mol⁻¹ H: 1, C: 12, N: 14, O: 16, Br: 80)}

Given below are two statements :
Statement I: Sublimation is used for the separation and purification of compounds with low melting point.
Statement II: The boiling point of a liquid increases as the external pressure is reduced.
In the light of the above statements, choose the correct answer from the options given below :
'x' is the product from propenenitrile + $SnCl_2/HCl$ followed by hydrolysis. 'y' is the product from but-2-ene by ozonolysis. Which product is not obtained when 'x' and 'y' react in alkali with heating?
In the given electrochemical cell, $Ag(s) | AgCl(s) | FeCl₂(aq), FeCl₃(aq) | Pt(s)$ at 298 K, the cell potential (E___cell) will increase when:
A. Concentration of Fe²⁺ is increased.
B. Concentration of Fe³⁺ is decreased.
C. Concentration of Fe²⁺ is decreased.
D. Concentration of Fe³⁺ is increased.
E. Concentration of Cl⁻ is increased.
Choose the correct answer from the options given below :
Among the following oxides of 3d elements, the number of mixed oxides are ____________.
\[ \mathrm{Ti_2O_3,\ V_2O_4,\ Cr_2O_3,\ Mn_3O_4,\ Fe_3O_4,\ Fe_2O_3,\ Co_3O_4} \]
[Ni(PPh$_3$)$_2$Cl$_2$] is a paramagnetic complex. Identify the {INCORRECT statements about this complex. A. The complex exhibits geometrical isomerism.
B. The complex is white in colour.
C. The calculated spin-only magnetic moment of the complex is $2.84$ BM.
D. The calculated CFSE (Crystal Field Stabilization Energy) of Ni in this complex is $-0.8\Delta_o$.
E. The geometrical arrangement of ligands in this complex is similar to that in Ni(CO)$_4$.
Choose the correct answer from the options given below: