List of top Chemistry Questions asked in JEE Main

Match list I with list II:

List I		List II
A	K	I	Thermonuclear reactions
B	KCl	II	Fertilizer
C	KOH	III	Sodium potassium pump
D	Li	IV	Absorbent of CO2

Choose the correct answer from the options given below:

Thin layer chromatography of a mixture shows the following observation:

The correct order of elution in the silica gel column chromatography is .

Match list I with list II:

List I	Species	List II	Geometry/ Shape
A	H3 O+	I	Tetrahedral
B	Acetylide anion	II	Linera
C	NH4 +	III	Pyramidal
D	ClO2–	IV	Bent

Choose correct answer from the options given below:

Given below are two statements:
Statement I: Methane and steam passed over a heated Ni catalyst produces hydrogen gas.
Statement II: Sodium nitrate reacts with NH\(_4\)Cl to give H\(_2\)O and NaCl.

The set which does not have ambidentate ligands (labeled as (i)) is:

Arrange the following compounds in increasing order of rate of aromatic electrophilic substitution reaction:

Find out the correct statement from the options given below for the above 2 reactions.

For elements B, C, N, Li, Be, O and F, the correct order of first ionization enthalpy is:

In the extraction process of copper, the product obtained after carrying out the reactions \[ \text{CuO} + \text{H}_2 \rightarrow \text{Cu} + \text{H}_2 \text{O} \] is called:

Given below are two statements:
Statement I: If BOD value is 4 ppm and dissolved oxygen is 8 ppm, it is a good quality water.
Statement II: If the concentration of zinc and nitrate is 5 ppm, then it can be used as good quality water.

In the above reaction 'A' and 'B' are:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: In the photoelectric effect electrons are ejected from the metal surface as soon as the beam of light of frequency greater than threshold frequency strikes the surface.
Reason R: When the photon of any energy strikes an electron in the atom transfer of energy from the photon to the electron takes place.

The complex that dissolves in water is:

Solid fuel used in rocket is a mixture of Fe₂O₃ and Al (in ratio 1 : 2) the heat evolved (KJ) per gram of the mixture is ______ (Nearest integer)
Given \(\Delta H_f^{\circ}(Al_2O_3) = -1700 \, \text{KJ mol}^{-1}\)
\(\Delta H_f^{\circ}(Fe_2O_3) = -840 \, \text{KJ mol}^{-1}\) }

A mixture of 1 mole of H₂O and 1 mole of CO is taken in a 10 liter container and heated to 725 K. At equilibrium, 10 M of water by mass reacts with carbon monoxide according to the equation: \[ CO(g) + H_2O(g) \rightleftharpoons CO_2(g) + H_2(g) \] The equilibrium constant \( K_c \times 10^7 \) for the reaction is ______

An atomic substance A of molar mass 12 g mol$^{-1}$ has a cubic crystal structure with edge length of 300 pm. The no. of atoms present in one unit cell of A is _____ (Nearest integer)

The ratio of spin-only magnetic moment values \( \mu_{\text{eff}}[Cr(CN)_6]^{3-}/\mu_{\text{eff}}[Cr(H_2O)_6]^{3+} \) is_____

A solution of sugar is obtained by mixing 200g of its 25% solution and 500g of its 40% solution (both by mass). The mass percentage of the resulting sugar solution is ______ (Nearest integer)

0.004 M K₂SO₄ solution is isotonic with 0.01 M glucose solution. Percentage dissociation of K₂SO₄ is______ (Nearest integer)

The number of hyperconjugation structures involved to stabilize carbocation formed in the below reaction is _______

The above reaction was studied at 300 K by monitoring the concentration of FeSO₄, in which initial concentration was 10 M and after half an hour became 8.8 M. The rate of production of Fe₂(SO₄)₃ is _____ × 10⁻⁶ mol L⁻¹ s⁻¹

In an electrochemical reaction of lead, at standard temperature, if \( E^{\circ}(\text{Pb}^{2+}/\text{Pb}) = m \) volt and \( E^{\circ}(\text{Pb}^{4+}/\text{Pb}^{2+}) = n \) volt, then the value of \( E^{\circ}(\text{Pb}^{4+}/\text{Pb}) \) is given by \( m - xn \). The value of \( x \) is ____

The ratio x/y on completion of the above reaction is _____

25 mL of silver nitrate solution (1M) is added dropwise to 25 mL of potassium iodide (1.05 M) solution. The ions(s) present in very small quantity in the solution is/are: