List of top Chemistry Questions asked in JEE Main

The correct decreasing order of energy for the orbitals having, following set of quantum numbers:
(A) n = 3, l = 0, m = 0
(B) n = 4, l = 0, m = 0
(C) n = 3, l = 1, m = 0
(D) n = 3, l = 2, m = 1
\(BeO\) reacts with \(HF\) in presence of ammonia to give \([A]\) which on thermal decomposition produces \([B]\) and ammonium fluoride. Oxidation state of Be in \([A]\) is _______
100 g of an ideal gas is kept in a cylinder of 416 L volume at 27°C under 1.5 bar pressure. The molar mass of the gas is ________ g mol–1. (Nearest integer). (Given : R = 0.083 L bar K–1 mol–1)

The number of molecules(s) or ions(s) from the following having non-planar structure is ____.
\(NO^-_3, H_2O_2, BF_3, PCl_3, XeF_4, SF_4, XeO_3, PH^+_4, SO3,[Al(OH)_4]^-\)

Ionic radii of cation A+ and anion B– are 102 and 181 pm, respectively. These ions are allowed to crystallize into an ionic solid. This crystal has cubic close packing for B–. A+ is present in all octahedral voids. The edge length of the unit cell of the crystal AB is _____pm. (Nearest integer)
Which of the given reactions is not an example of a disproportionation reaction?
Observe structures of the following compounds

The total number of structures/compounds which possess asymmetric carbon atoms is _____.
The products obtained from a reaction of hydrogen peroxide and acidified potassium permanganate are

A solution of Fe2(SO4)3 is electrolyzed for ‘x’ min with a current of 1.5 A to deposit 0.3482 g of Fe. The value of x is _______. [nearest integer]

Given : 1 F = 96500 C mol–1. 

Atomic mass of Fe = 56 g mol–1

pH value of 0.001 M NaOH solution is _______.

4.0 moles of argon and 5.0 moles of PCl5 are introduced into an evacuated flask of 100 litre capacity at 610 K. The system is allowed to equilibrate. At equilibrium, the total pressure of mixture was found to be 6.0 atm. The Kp for the reaction is
 [Given : R = 0.082 L atm K–1 mol–1 ]
The major product in the given reaction is
Question Reaction
The Novolac polymer has mass of 963 g. The number of monomer units present in it are
Which of the following sets are correct regarding polymer?
  1. Copolymer : Buna-S
  2. Condensation polymer : Nylon-6,6
  3. Fibres : Nylon-6,6
  4. Thermosetting polymer : Terylene
  5. Homopolymer : Buna-N
Choose the correct answer from given options below
Which of the following ketone will NOT give enamine on treatment with secondary amines? [where t-Bu is –C(CH3)3]
Given below are two statements: one is labelled as Assertion A and, the other is labelled as Reason R.
Assertion A: [6] Annulene, [8] Annulene and cis-[10] Annulene, are respectively aromatic, not-aromatic and aromatic.
Reason R: Planarity is one, of the requirements of aromatic systems.
In the light of the above statements, choose the most appropriate answer from the options given below.
The rate constant for a first order reaction is given by the following equation :
\(ln\ k=33.24−\frac {2.0×10^4\ K}{T}\)
The activation energy for the reaction is given by ______ \(kJ mol^{–1}\). (In nearest integer)
(Given : \(R = 8.3 JK^{–1} mol^{–1}\))
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. 
Assertion A : \(LiF\) is sparingly soluble in water.
Reason R : The ionic radius of \(Li^+\) ion is smallest among its group members, hence has least hydration enthalpy.
In the light of the above statements, choose the most appropriate answer from the options given below.
Which statement is not true with respect to nitrate ion test?

The normality of H2SO4 in the solution obtained on mixing 100 mL of 0.1 M H2SO4 with 50 mL of 0.1 M NaOH is ________ × 10–1 N. (Nearest Integer)

Given below are two statements:
Statement I : According to the Ellingham diagram, any metal oxide with higher ΔG° is more stable than the one with lower ΔG°.
Statement II :The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram.
In the light of the above statements, choose the most appropriate answer from the options given below
Among the following ores Bauxite, Siderite, Cuprite, Calamine, Haematite, Kaolinite, Malachite, Magnetite, Sphalerite, Limonite, Cryolite, the number of principal ores of iron is____.
Number of lone pair(s) of electrons on central atom and the shape of BrF3 molecule respectively, are
The molar heat capacity for an ideal gas at constant pressure is 20.785 J K–1 mol–1. The change in internal energy is 5000 J upon heating it from 300 K to 500 K. The number of moles of the gas at constant volume is _____. (Nearest integer)
(Given : R = 8.314 JK-1mol-1).
The hybridization of P exhibited in \(PF_5\) is \(sp_xd_y\). The value of y is _____ .