List of top Chemistry Questions asked in JEE Main

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Heavy water is used for the study of reaction mechanism.
Reason (R): The rate of reaction for the cleavage of O-H bond is slower than that of O-D bond.
Match List - I with List - II : List - I (Chemicals)
(a) Alcoholic potassium hydroxide
(b) Pd/BaSO₄
(c) BHC (Benzene hexachloride)
(d) Polyacetylene List - II (Use/Preparation/Constituent)
(i) electrodes in batteries
(ii) obtained by addition reaction
(iii) used for β-elimination reaction
(iv) Lindlar's Catalyst
The incorrect statement is :
Statement I : Colourless cupric metaborate is reduced to cuprous metaborate in a luminous flame. Statement II : Cuprous metaborate is obtained by heating boric anhydride and copper sulphate in a non-luminous flame.
The correct order of following 3d metal oxides, according to their oxidation numbers is :
(a) $CrO_3$
(b) $Fe_2O_3$
(c) $MnO_2$
(d) $V_2O_5$
(e) $Cu_2O$

Arrange the following conformational isomers of n-butane in order of their increasing potential energy : 
 

The solubility of AgCN in a buffer solution of pH=3 is x. The value of x is : [Assume : No cyano complex is formed ; $K_{sp}(\text{AgCN}) = 2.2 \times 10^{-16}$ and $K_a(\text{HCN}) = 6.2 \times 10^{-10}$]

The correct order of acid character of the following compounds is : 
I: Phenol, II: p-Nitrobenzoic acid, III: Benzoic acid, IV: p-Toluic acid 

In the following sequence of reactions the P is: 

The incorrect expression among the following is :
(A) $HOCl + H _{2} O _{2} \rightarrow H _{3} O ^{+}+ Cl ^{-}+ O _{2}$
(B) $I _{2}+ H _{2} O _{2}+2 OH ^{-} \rightarrow 2 I ^{-}+2 H _{2} O + O _{2}$
Choose the correct option.
Calgon is used for water treatment. Which of the following statement is $NOT$ true about Calgon?
Which of the glycosidic linkage between galactose and glucose is present in lactose ?
According to molecular orbital theory, the species among the following that does not exist is :
The gas 'A' is having very low reactivity reaches to stratosphere. It is non-toxic and non-flammable but dissociated by UV-radiations in stratosphere. The intermediates formed initially from the gas 'A' are:

The Major Product in the above reaction is : 

 

An organic compound "A" on treatment with benzene sulphonyl chloride gives compound B. B is soluble in dil. NaOH solution. Compound A is :
Match List - I and List - II. List - I: (a) Valium, (b) Morphine, (c) Norethindrone, (d) Vitamin B12 List - II: (i) Antifertility drug, (ii) Pernicious anaemia, (iii) Analgesic, (iv) Tranquilizer
Given below are two statements :
Statement I : The process of producing syn-gas is called gasification of coal.
Statement II : The composition of syn-gas is \( \text{CO} + \text{CO}_2 + \text{H}_2 \) (1 : 1 : 1).
In the light of the above statements, choose the most appropriate answer from the options given below :
BOD values (in ppm) for clean water (A) and polluted water (B) are expected respectively as :
Which one of the following \( 0.10 \, \text{M} \) aqueous solutions will exhibit the largest freezing point depression ?
What are the products formed in sequence when excess of \(CO_2\) is passed in slaked lime ?
Given below are two statements : Statement I : An allotrope of oxygen is an important intermediate in the formation of reducing smog. Statement II : Gases such as oxides of nitrogen and sulphur present in troposphere contribute to the formation of photochemical smog. In the light of the above statements, choose the correct answer from the options given below :
Water does not produce CO on reacting with:


Consider the following reaction, the major product 'P' is: