List of top Chemistry Questions asked in JEE Main

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

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: A mixture contains benzoic acid and naphthalene. The pure benzoic acid can be separated out by the use of benzene.

Reason R: Benzoic acid is soluble in hot water.

In the light of the above statements, choose the most appropriate answer from the options given below.

The standard entropy change for the reaction \(4Fe(s) + 3O_2(g) → 2Fe_2O_3(s)\) is \(–550\ J K^{–1}\) at \(298\ K\). The temperature in K at which the reaction attains equilibrium is ______. (Nearest Integer)
[Given: The standard enthalpy change for the reaction is \(–165\ kJmol^{–1}\)].

Metal deficiency defect is shown by \(Fe_{0.93}O\). In the crystal, some \(Fe^{2+}\) cations are missing and loss of positive charge is compensated by the presence of \(Fe^{3+}\) ions. The percentage of \(Fe^{2+}\) ions in the \(Fe_{0.93}O\) crystals is ______ . (Nearest integer)

The dark purple colour of \(KMnO_4\) disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is :

Which one of the following is a reducing sugar?

The number of oxygens present in a nucleotide formed from a base, that is present only in RNA is ________.

Which one of the following is NOT a copolymer?

Match List-I with List-II

Choose the correct answer from the options given below:

The correct structure of product ‘A’ formed in the following reaction,

(Ph is – C₆H₅) is

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Experimental reaction of \(CH_3Cl\) with aniline and anhydrous \(AlCl_3\) does not give o and p-methylaniline.
Reason (R): The \(–NH_2\)group of aniline becomes deactivating because of salt formation with anhydrous \(AlCl_3\) and hence yields m-methyl aniline as the product.
In the light of the above statements, choose the most appropriate answer from the options given below :

Which of the following is a correct statement?

The mixture of chloroxylenol and terpineol is an example of

Isobutyraldehyde on reaction with formaldehyde and K₂CO₃ gives compound ‘A’. Compound ‘A’ reacts with KCN and yields compound ‘B’, which on hydrolysis gives a stable compound ‘C’. The compound ‘C’ is

Stearic acid and polyethylene glycol react to form which one of the following soap/s detergents?

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Dacron is an example of polyester polymer.
Reason R : Dacron is made up of ethylene glycol and terephthalic acid monomers.
In the light of the above statements, choose the most appropriate answer from the options given below.

The eutrophication of water body results in:

Fe³⁺ cation gives a Prussian blue precipitate on addition of potassium ferrocyanide solution due to the formation of:

On the surface of polar stratospheric clouds, hydrolysis of chlorine nitrate gives A and B while its reaction with HCl produces B and C. A, B and C are, respectively

Concentrated \(HNO_3\) reacts with Iodine to give

100 mL of 5% (w/v) solution of NaCl in water was prepared in 250 mL beaker. Albumin from the egg was poured into NaCl solution and stirred well. This resulted in a/an :

The quantity of electricity of Faraday needed to reduce \(1\) mol of \(Cr_2O_7^{2-}\)to \(Cr^{3+}\) is