List of top Chemistry Questions

When Ethane-1,2-diamine is added progressively to an aqueous solution of Nickel (II) chloride, the sequence of colour change observed will be:

Match List - I with List - II.

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

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


 

For the reaction, $$ H_2(g) + I_2(g) \rightleftharpoons 2HI(g) $$ Attainment of equilibrium is predicted correctly by: 

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:

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:

Given below are two statements: 

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:

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:
Find the compound \( A \) from the following reaction sequences: \[ A \xrightarrow{\text{aqua regia}} B \xrightarrow{(1) \, \text{KNO}_3, \, \text{NH}_4\text{OH}} \text{yellow ppt}. \]

Match List - I with List - II:

List - I

List - II

(A) Adenine

(I)

(B) Cytosine

(II)

(C) Thymine

(III)

(D) Uracil

(IV)

 

Choose the correct answer from the options given below:

Which of the following electrolyte can be used to obtain \( \text{H}_2\text{S}_2\text{O}_8 \) by the process of electrolysis?

The compounds which give positive Fehling's test are:
The compounds which give positive Fehling's test are:
Choose the CORRECT answer from the options given below:

In which of the following complexes the CFSE, \(\Delta_0\) will be equal to zero?

From the magnetic behaviour of \([NiCl_4]^{2-}\) (paramagnetic) and [Ni\((CO)_4\)] (diamagnetic), choose the correct geometry and oxidation state.

The incorrect statements regarding geometrical isomerism are: 
(A) Propene shows geometrical isomerism. 
(B) Trans isomer has identical atoms/groups on the opposite sides of the double bond. 
(C) Cis-but-2-ene has higher dipole moment than trans-but-2-ene. 
(D) 2-methylbut-2-ene shows two geometrical isomers. 
(E) Trans-isomer has lower melting point than cis isomer. 
 

The number of molecules/ions that show linear geometry among the following is _____. SO₂, BeCl₂, CO₂, N₃⁻, NO₂, F₂O, XeF₂, NO₂⁺, I₃⁻, O₃

The molecule A changes into its isomeric form B by following a first order kinetics at a temperature of 1000 K. If the energy barrier with respect to reactant energy for such isomeric transformation is 191.48 kJ mol\(^{-1}\) and the frequency factor is \(10^{20}\), the time required for 50% molecules of A to become B is ________________________ picoseconds (nearest integer). [R = 8.314 J K\(^{-1}\) mol\(^{-1}\)]

Consider the following compound (X):
 
The most stable and least stable carbon radicals, respectively, produced by homolytic cleavage of corresponding C - H bond are:

Consider the following equilibrium,

CO(g) + 2H2(g) ↔ CH3OH(g)

0.1 mol of CO along with a catalyst is present in a 2 dm3 flask maintained at 500 K. Hydrogen is introduced into the flask until the pressure is 5 bar and 0.04 mol of CH3OH is formed. The Kp is ____ × 10-3 (nearest integer).

Given: R = 0.08 dm3 bar K-1mol-1

Assume only methanol is formed as the product and the system follows ideal gas behaviour.

0.1 mol of the following given antiviral compound (P) will weigh .........x $ 10^{-1} $ g. 

For the reaction $ A \rightarrow $ products, 

The reaction was started with 2.5 mol L\(^{-1}\) of A.

Consider the following sequence of reactions :

Molar mass of the product formed (A) is ______ g mol\(^{-1}\).

Consider the following electrochemical cell at standard condition. $$ \text{Au(s) | QH}_2\text{ | QH}_X(0.01 M) \, \text{| Ag(1M) | Ag(s) } \, E_{\text{cell}} = +0.4V $$ The couple QH/Q represents quinhydrone electrode, the half cell reaction is given below: $$ \text{QH}_2 \rightarrow \text{Q} + 2e^- + 2H^+ \, E^\circ_{\text{QH}/\text{Q}} = +0.7V $$