List of top Chemistry Questions

Given below are two statements:
Statement (I): On nitration of m-xylene with \( \text{HNO}_3 \), \( \text{H}_2\text{SO}_4 \), followed by oxidation, 4-nitrobenzene-1, 3-dicarboxylic acid is obtained as the major product.
Statement (II): CH\(_3\) group is o/p-directing while NO\(_2\) group is m-directing group.
In the light of the above statements, choose the correct answer from the options given below:
Statement – 1: First ionization energy of Ge is greater than Si.
Statement – 2: First ionization energy of Pb is greater than Sn.
The heat of formation of \( \text{SO}_2(g) \) is given by: \[ S(g) + \frac{3}{2} O_2(g) \rightarrow SO_3(g) + 2x \, \text{kcal} \] \[ SO_2(g) + \frac{1}{2} O_2(g) \rightarrow SO_3(g) + y \, \text{kcal} \]
When Ethane-1,2-diamine is added progressively to an aqueous solution of Nickel (II) chloride, the sequence of colour change observed will be:

The structure of the major product formed in the following reaction is: 

In the given structure, number of \( sp \) and \( sp^2 \) hybridized carbon atoms present respectively are:

Choose the correct statements.
(A) Weight of a substance is the amount of matter present in it.
(B) Mass is the force exerted by gravity on an object.
(C) Volume is the amount of space occupied by a substance.
(D) Temperatures below \(0^\circ\)C are possible in Celsius scale, but in Kelvin scale negative temperature is not possible.
(E) Precision refers to the closeness of various measurements for the same quantity.
Choose the correct answer from the options given below:

Match List - I with List - II: 

 

Based on the data given below: \[ E^\circ_{\text{Cr}_2\text{O}_7^{2-}/\text{Cr}^{3+}} = 1.33 \, \text{V}, \quad E^\circ_{\text{Cl}_2/\text{Cl}^-} = 1.36 \, \text{V}, \quad E^\circ_{\text{MnO}_4^-/\text{Mn}^{2+}} = 1.51 \, \text{V}, \quad E^\circ_{\text{Cr}^{3+}/\text{Cr}} = -0.74 \, \text{V}. \] The strongest reducing agent is:

Given below are two statements: 
Statement (I): The first ionization energy of Pb is greater than that of Sn. 
Statement (II): The first ionization energy of Ge is greater than that of Si. 

In light of the above statements, choose the correct answer from the options given below:

Given below are two statements: 
Statement I: Experimentally determined oxygen-oxygen bond lengths in the \( O_2 \) are found to be the same and the bond length is greater than that of a \( O=O \) (double bond) but less than that of a single \( O-O \) bond. 
Statement II: The strong lone pair-lone pair repulsion between oxygen atoms is solely responsible for the fact that the bond length in ozone is smaller than that of a double bond \( O=O \) but more than that of a single bond \( O-O \). 
In light of the above statements, choose the correct answer from the options given below:

Identify correct statement/s: 
(A) \( -\text{OCH}_3 \) and \( -\text{NHCOCH}_3 \) are activating groups. 
(B) \( -\text{CN} \) and \( -\text{OH} \) are meta directing groups. 
(C) \( -\text{CN} \) and \( -\text{SO}_3\text{H} \) are meta directing groups. 
(D) Activating groups act as ortho- and para-directing groups. 
(E) Halides are activating groups. 

Choose the correct answer from the options given below:

The elemental composition of a compound is 54.2% C, 9.2% H, and 36.6% O. If the molar mass of the compound is 132 g/mol, the molecular formula of the compound is:

The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values, predict the group in which the above element is present:

Match List - I with List - II: 

Choose the correct answer from the options given below:
 

For hydrogen atom, the orbital/s with lowest energy is/are:
The correct option with order of melting points of the pairs (Mn, Fe), (Tc, Ru) and (Re, Os) is:
Which of the following mixing of 1M base and 1M acid leads to the largest increase in temperature?

Given below are two statements: 




In light of the above statements, choose the correct answer from the options given below:

Find the compound \( A \) from the following reaction sequences: \[ A \xrightarrow{\text{aqua regia}} B \xrightarrow{(1) \, \text{KNO}_3, \, \text{NH}_4\text{OH}} \text{yellow ppt}. \]
500 J of energy is transferred as heat to 0.5 mol of Argon gas at 298 K and 1.00 atm. The final temperature and the change in internal energy respectively are: Given \( R = 8.3 \, {J K}^{-1} \, {mol}^{-1} \) Choose the correct answer from the options given below:
Match List - I with List - II.

\[ \begin{array}{|c|c|} \hline \text{List - I} & \text{List - II} \\ \hline \text{(A) } \text{Ti}^{3+} & \text{(I) } 3.87 \\ \text{(B) } \text{V}^{2+} & \text{(II) } 0.00 \\ \text{(C) } \text{Ni}^{2+} & \text{(III) } 1.73 \\ \text{(D) } \text{Sc}^{3+} & \text{(IV) } 2.84 \\ \hline \end{array} \]

The conditions and consequences that favour the \( t_{2g}^3 e_g^1 \) configuration in a metal complex are:
The reaction \( {A}_2 + {B}_2 \to 2{AB} \) follows the mechanism: \[ {A}_2 \xrightarrow{k_1} {A} + {A} \ ({fast}) \quad {A} + {B}_2 \xrightarrow{k_2} {AB} + {B} \ ({slow}) \quad {A} + {B} \to {AB} \ ({fast}) \] The overall order of the reaction is:
Match List - I with List - II: List - I: (A) Amylase
(B) Cellulose
(C) Glycogen
(D) Amylopectin
List - II: (I) \( \beta \)-C1-C4 plant
(II) \( \alpha \)-C1-C4 animal
(III) \( \alpha \)-C1-C4 \( \alpha \)-C1-C6 plant
(IV) \( \alpha \)-C1-C4 plant
Choose the correct answer from the options given below: