List of top Chemistry Questions

In Hall - Heroult process, the following is used for reducing Al₂O₃ :-

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Sodium is about 30 times as abundant as potassium in the oceans.
Reason R : Potassium is bigger in size than sodium.
In the light of the above statements, choose the correct answer from the options given below

Which of these reactions is not a part of breakdown of ozone in stratosphere?

The correct order of reactivity of following haloarenes towards nucleophilic substitution with aqueous NaOH is 

Choose the correct answer from the options given below:

The descending order of acidity for the following carboxylic acid is-
A. CH₃COOH
B. F₃C-COOH
C. CICH₂-COOH
D. FCH₂-COOH
E. BrCH₂-COOH
Choose the correct answer from the options given below:

The product (P) formed from the following multistep reaction is:

Match List l with List ll.

List I Natural amino acid	List II One letter code
(I) Glutamic acid	(a) Q
(II) Glutamine	(b) W
(III) Tyrosine	(c) E
(IV) Tryptophan	(d) Y

Choose the correct answer from the options given below:

Given below are two statements:
Statement I: In redox titration, the indicators used are sensitive to change in pH of the solution.
Statement II: In acid-base titration, the indicators used are sensitive to change in oxidation potential.
In the light of the above statements, choose the most appropriate answer from the options given below

The number of species from the following carrying a single lone pair on central atom Xenon is ______ .
XeF₅⁺, XeO₃, XeO₂F₂, XeF₅^-, XeO₃F₂, XeOF₄, XeF₄

For complete combustion of ethene,
\(C_2H_4(g) + 3O_2(g) \longrightarrow 2CO_2(g) + 2H_2O (l)\)
the amount of heat produced as measured in bomb calorimeter is 1406 kJ mol^-1 at 300K. The minimum value of \(T\Delta S\) needed to reach equilibrium is (-) _____ . kJ.(Nearest integer)
Given: R = 8.3 J K^-1 mol^-1

If the boiling points of two solvents X and Y (having same molecular weights) are in the ratio 2:1 and their enthalpy of vaporizations are in the ratio 1:2, then the boiling point elevation constant of X is m times the boiling point elevation constant of Y. The value of m is ______ (nearest integer).

The number of incorrect statements from the following is _____
A. The electrical work that a reaction can perform at constant pressure and temperature is equal to the reaction Gibbs energy.
B. E°_cell is dependent on the pressure.
C. dE^θ cell/dT = Δ_rS^θ/nF
D. A cell is operating reversibly if the cell potential is exactly balanced by an opposing source of potential difference.

Coagulating value of the electrolytes AlCl₃ and NaCl for As₂S₃ are 0.09 and 50.04 respectively. The coagulating power of AlCl₃ is x times the coagulating power of NaCl. The value of x is ______ .

Given below are two reactions, involved in the commercial production of dihydrogen (H₂). The two reactions are carried out at temperature “T₁ ” and “T₂ ” respectively
\(C(S)+H_2O(g)\underrightarrow {T_1}\;CO(g)+H_2(g)\)
\(CO(g)+H_2O(g)\underrightarrow{T_2}\;CO_2(g)+H_2(g)\)
The temperature \(T_1\) and \(T_2\) are correctly related as 

Lime reacts exothermally with water to give ‘A’ which has low solubility in water. Aqueous solution of ‘A’ is often used for the test of CO2 , a test in which insoluble B is formed. If B is further reacted with CO2 then soluble compound is formed ‘A’ is

Which of the following statements are correct?
(A) The M³⁺/M²⁺ reduction potential for iron is greater than manganese 
(B) The higher oxidation states of first row dblock elements get stabilized by oxide ion. 
(C) Aqueous solution of Cr²⁺ can liberate hydrogen from dilute acid. 
(D) Magnetic moment of V²⁺ is observed between 4.4-5.2 BM Choose the correct answer from the options given below: 

The pair of compounds from the following pairs having both the compounds with net non-zero dipole moment is

Identify the correct order of reactivity for the following pairs towards the respective mechanism




Choose the correct answer from the options given below :

The major product ‘P’ formed in the given reaction is

Suitable reaction condition for preparation of Methyl phenyl ether is

Isomeric amines with molecular formula C₈ H₁₁N give the following tests
Isomer (P) ⇒ Can be prepared by Gabriel phthalimide synthesis
Isomer (Q) ⇒ Reacts with Hinsberg’s reagent to give solid insoluble in NaOH
Isomer (R) ⇒ Reacts with HONO followed by β-naphthol in NaOH to give red dye.
Isomers (P), (Q) and (R) respectively are

Match List I with List II

List-I	Polymer	List-II	Type/ Class
(A)	Nylon-2-Nylon-6	(I)	Thermosetting polymer
(B)	Buna-N	(II)	Biodegradable polymer
(C)	Urea-formaldehyde	(III)	Synthetic rubber resin
(D)	Dacron	(IV)	Polyester

Choose the correct answer from the options given below:

The number of incorrect statement/s about the black body from the following is _______
(A) Emit or absorb energy in the form of electromagnetic radiation 
(B) Frequency distribution of the emitted radiation depends on temperature
(C) At a given temperature, intensity vs frequency curve passes through a maximum value 
(D) The maximum of the intensity vs frequency curve is at a higher frequency at higher temperature compared to that at lower temperature

The number of correct statement/s involving equilibria in physical process from the following is
(A) Equilibrium is possible only in a closed system at a given temperature 
(B) Both the opposing processes occur at the same rate. 
(C) When equilibrium is attained at a given temperature, the value of all its parameters became equal 
(D) For dissolution of solids in liquids, the solubility is constant at a given temperature

\(FeO^{2-}_4+\underrightarrow{2.2v}\;Fe^{3+}\underrightarrow{+0.70v}\;Fe^{2+}\underrightarrow{-0.45v}\;Fe^0\)
\(E^0_{FeO_4^{2+}}\; is \;x × 10^{-3} V\). The Value of \(x\) is __