List of top Chemistry Questions on Redox reactions asked in JEE Main

The heat of formation of $ \text{SO}_2(g) $ is given by: $$ S(g) + \frac{3}{2} O_2(g) \rightarrow SO_3(g) + 2x \, \text{kcal} $$ $$ SO_2(g) + \frac{1}{2} O_2(g) \rightarrow SO_3(g) + y \, \text{kcal} $$

Choose the correct answer from the options given below:

Which of the following oxidation reactions are carried out by both $ K_2Cr_2O_7 $ and $ KMnO_4 $ in acidic medium?
A. $ I^- \rightarrow I_2 $
B. $ S^{2-} \rightarrow S $
C. $ Fe^{2+} \rightarrow Fe^{3+} $
D. $ I^- \rightarrow IO_3^- $
E. $ S_2O_3^{2-} \rightarrow SO_4^{2-} $
Choose the correct answer from the options given below:

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 standard reduction potential values of some of the p-block ions are given below. Predict the one with the strongest oxidizing capacity.

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 heat of formation of $ \text{SO}_2(g) $ is given by: \[ S(g) + \frac{3}{2} O_2(g) \rightarrow SO_3(g) + 2x \, \text{kcal} \] \[ SO_2(g) + \frac{1}{2} O_2(g) \rightarrow SO_3(g) + y \, \text{kcal} \]

The product (A) formed in the following reaction sequence is:

For a $ {Mg} | {Mg}^{2+}(aq) || {Ag}^{+}(aq) | {Ag} $, the correct Nernst Equation is:

The steam volatile compounds among the following are:

Choose the correct answer from the options given below:

Match the LIST-I with LIST-II (Redox Reactions).

\[ \begin{array}{|c|c|} \hline \textbf{LIST-I (Redox Reaction)} & \textbf{LIST-II (Type of Redox Reaction)} \\ \hline A. \, CH_4(g) + 2O_2(g) \rightarrow CO_2(g) + 2H_2O(l) & I. \, \text{Disproportionation reaction} \\ B. \, 2NaH(s) \rightarrow 2Na(s) + H_2(g) & II. \, \text{Combination reaction} \\ C. \, V_2O_5(s) + 5Ca(s) \rightarrow 2V(s) + 5CaO(s) & III. \, \text{Decomposition reaction} \\ D. \, 2H_2O(aq) \rightarrow 2H_2(g) + O_2(g) & IV. \, \text{Displacement reaction} \\ \hline \end{array} \]

Choose the correct answer from the options given below:

Which of the following oxidation reactions are carried out by both $ K_2Cr_2O_7 $ and $ KMnO_4 $ in acidic medium? A. $ I^- \rightarrow I_2 $ B. $ S^{2-} \rightarrow S $ C. $ Fe^{2+} \rightarrow Fe^{3+} $ D. $ I^- \rightarrow IO_3^- $ E. $ S_2O_3^{2-} \rightarrow SO_4^{2-} $ Choose the correct answer from the options given below:

Thiosulphate reacts differently with iodine and bromine in the reaction given below:
$$ 2S_2O_3^{2-} + I_2 \rightarrow S_4O_6^{2-} + 2I^- $$ $$ S_2O_3^{2-} + 5Br_2 + 5H_2O \rightarrow 2SO_4^{2-} + 4Br^- + 10H^+ $$
Which of the following statements justifies the above dual behaviour of thiosulphate?

Total number of species from the following which can undergo disproportionation reaction _______.
$\text{H}_2\text{O}_2, \text{ClO}_3^-, \text{P}_4, \text{Cl}_2, \text{Ag}, \text{Cu}^{+1}, \text{F}_2, \text{NO}_2, \text{K}^+$

In acidic medium, $ K_2Cr_2O_7 $ shows oxidizing action as represented in the half-reaction: $Cr_2O_7^{2-} + XH^+ + Ye^- \rightarrow 2A + ZH_2O$
$ X $, $ Y $, $ Z $, and $ A $ are respectively:

1 mole of PbS is oxidised by “X” moles of O₃>to get “Y” moles of O2. X + Y = __________

\[ 2 \text{MnO}_4^{-} + b \text{I}^{-} + c \text{H}_2\text{O} \rightarrow x \text{I}_2 + y \text{MnO}_2 + z \text{OH}^{-} \]
If the above equation is balanced with integer coefficients, the value of $ z $ is $ \_\_\_\_\_\_ $.

Number of moles of $ H^+ $ ions required by 1 mole of $ MnO_4^- $ to oxidise oxalate ion to $ CO_2 $ is ____.

When $ \text{MnO}_2 $ and $ \text{H}_2\text{SO}_4 $ is added to a salt (A), the greenish yellow gas liberated as salt (A) is:

Only $ 2 \, \text{mL} $ of $ \text{KMnO}_4 $ solution of unknown molarity is required to reach the end point of a titration of $ 20 \, \text{mL} $ of oxalic acid ($ 2 \, \text{M} $) in acidic medium. The molarity of $ \text{KMnO}_4 $ solution should be ______ $ \text{M} $.

The number of ions from the following that have the ability to liberate hydrogen from a dilute acid is _______. Ti²⁺, Cr²⁺ and V²⁺.

Consider the following redox reaction:\[\text{MnO}_4^- + \text{H}^+ + \text{H}_2 \text{C}_2 \text{O}_4 \rightleftharpoons \text{Mn}^{2+} + \text{H}_2 \text{O} + \text{CO}_2\]The standard reduction potentials are given as below (E$_\text{red}$):\[E^\circ_{\text{MnO}_4^-/\text{Mn}^{2+}} = +1.51 \, \text{V}\]\[E^\circ_{\text{CO}_2/\text{H}_2 \text{C}_2 \text{O}_4} = -0.49 \, \text{V}\]If the equilibrium constant of the above reaction is given as $K_\text{eq} = 10^x$, then the value of (x = ________ ) (nearest integer).