List of top Chemistry Questions

Which of the following is NOT correctly matched?
Conversion of X to Y is an example of
Conversion of X to Y is an example of
Which of the following is correct statement?
Polymers that can be softened on heating and hardened on cooling are called
Which complex among the following is most paramagnetic?
The basicity of H$_3$PO$_2$, H$_3$PO$_3$, H$_3$PO$_4$ respectively is
Which of the following solutions is used in the styptic action which prevents bleeding of blood?
‘A’ is a protecting colloid. The following data is obtained for preventing the coagulation of 10 mL of gold sol to which 1 mL of 10% NaCl is added. What is the gold number of ‘A’?
‘A’ is a protecting colloid.
Which of the following reactions of KMnO$_4$ occurs in acidic medium?
In water, which of the following gases has the highest Henry’s law constant at 293 K?
Consider the cell reaction, at 300 K.
A\(^+ (aq)\) + B\(^3+\) (aq) \(\rightleftharpoons\) A\(^2+\) (aq) + B (g) Its \(E^\circ\) is 1.0 V. The \(\Delta_r H^\circ\) of the reaction is -163 kJ mol\(^{-1}\). What is \(\Delta_r S^\circ\) (in J K\(^{-1}\) mol\(^{-1}\)) of the reaction?
(F = 96500 C mol\(^{-1}\))
The rate constant of a first order reaction was doubled when the temperature was increased from 300 to 310 K. What is its approximate activation energy (in kJ mol\(^{-1}\))?
(R = 8.3 J mol\(^{-1}\) K\(^{-1}\), \(\log 2 = 0.3\))
What are X and Y respectively in the following reaction sequence?
X and Y respectively
Which one of the following alkali metals is the weakest reducing agent as per their \( E^\circ \) values?
Match the pollutant in List I with its maximum permissible limit in drinking water given in List II.

maximum permissible limit in drinking water

A vessel of volume \( V \) L contains an ideal gas at \( T(K) \). The vessel is partitioned into two equal parts. The volume (in L) and temperature (in K) in each part is respectively:
100 mL of 0.1 M \( Fe^{2+} \) solution was titrated with \( \frac{1}{60} \) M \( Cr_2O_7^{2-} \) solution in acid medium. What is the volume (in L) of \( Cr_2O_7^{2-} \) solution consumed?
Observe the following reaction: \[ ABO_3 (s) \xrightarrow{1000 K} AO (s) + BO_2 (g) \] The enthalpy change \( \Delta H \) for this reaction is \( x \) kJ mol\(^{-1} \). What is its \( \Delta U \) (in kJ mol\(^{-1}\)) at the same temperature? (R = 8.3 \text{ J mol}^{-1} \text{ K}^{-1})
The number of lone pairs of electrons on the central atom of \( BrF_5 \), \( XeO_3 \), \( SO_3 \) respectively are:
The shape of the colourless neutral gas formed on thermal decomposition of ammonium nitrate is:

What are Y and Z respectively in the following reaction sequence?

What are Y and Z respectively in the following reaction sequence
Hydrolysis of an alkyl bromide X (C\(_4\)H\(_9\)Br) follows first-order kinetics. Reaction of X with Mg in dry ether followed by treatment of D\(_2\)O gave Y. What is Y?
An alcohol \( X \) (\( C_4H_{10}O \)) does not give turbidity with conc. HCl and ZnCl\(_2\) at room temperature. \( X \) on reaction with reagent \( Y \) gives \( Z \). What are \( X \), \( Y \), and \( Z \) respectively?

What are X and Y respectively in the following reactions?

What are X and Y respectively in the following reactions

Which of the following sets of reagents convert toluene to benzaldehyde?