Chapter: Redox Reaction

The compound that cannot act both as oxidising and reducing agent is:

The redox reaction among the following is:

Which of the following reactions is an example of a redox reaction?

Copper becomes green when exposed to moist air for a long period. This is due to:

Which of the following chemical reactions depict the oxidizing beahviour of \(\begin{align}{{H}_{2}}S{{O}_{{4~}}}\end{align}\)?

Several blocks of magnesium are fixed to the bottom of a ship to

Which of the following is a redox reaction?

The oxidation states of iron atoms in compounds (A), (B) and (C), respectively, are x, y and z. The sum of x, y and z is __________.

(A)\(\begin{align}N{{a}_{4}}\left[ {Fe{{{\left( {CN} \right)}}_{5}}\left( {NOS} \right)} \right]\end{align}\) (B) \(\begin{align}N{{a}_{4}}\left[ {Fe{{O}_{4}}} \right]\text{ }\end{align}\) (C) \(\begin{align}[F{{e}_{2}}{{(CO)}_{9}}]\end{align}\)

The oxidation states of transition metal atoms in \(\begin{align}{{K}_{2}}C{{r}_{2}}{{O}_{7}}\end{align}\), \(\begin{align}KMn{{O}_{4}}\end{align}\) and \(\begin{align}{{K}_{2}}Fe{{O}_{4}}\end{align}\), respectively, are x, y and z. The sum of x, y and z is _______.

Oxidation number of potassium in \(\begin{align}{{K}_{2}}O,\text{ }{{K}_{2}}{{O}_{2}}\text{ }and\text{ }K{{O}_{2}}\end{align}\), respectively, is:

The oxidation states of Cr in \(\begin{align}\left[ {Cr{{{\left( {{{H}_{2}}O} \right)}}_{{6\text{ }}}}} \right]C{{l}_{3}},\text{ }\left[ {Cr{{{\left( {{{C}_{6}}{{H}_{6}}} \right)}}_{2}}} \right],~and\text{ }{{K}_{2}}\left[ {Cr{{{\left( {CN} \right)}}_{2}}{{{\left( O \right)}}_{2}}\left( {{{O}_{2}}} \right)\left( {N{{H}_{3}}} \right)} \right]\end{align}\) respectively are:

Amongst the following, identify the species with an atom in + 6 oxidation state:

Oxidation state of sulphur in anions \(\begin{align}~SO_{3}^{{2-}},\text{ }{{S}_{2}}O~_{4}^{{2-}}and~{{S}_{2}}O_{6}^{{2-}}\end{align}\) increases in the orders :

Consider the following equations:
\(\begin{align}2F{{e}^{{2+}}}+{{H}_{2}}{{O}_{2}}\to xA+yB\end{align}\) (in basic medium)
\(\begin{align}2MnO_{4}^{-}+6{{H}^{+}}+5{{H}_{2}}{{O}_{2}}\to x’C+y’D+z’E\end{align}\) (in acidic medium)
The sum of the stoichiometric coefficients x, y, x’, y’ and z’ for products A, B, C, D and E, respectively, is ___________.

An example of a disproportionation reaction is:

In order to oxidise a mixture of one mole of each of \(\begin{align}Fe{{C}_{2}}{{O}_{4}},~F{{e}_{{2\text{ }}}}{{\left( {{{C}_{2}}{{O}_{4}}} \right)}_{3}},\text{ }FeS{{O}_{4}}\text{ }and\text{ }F{{e}_{2}}{{\left( {S{{O}_{4}}} \right)}_{3}}\end{align}\) in acidic medium,
the number of moles of KMnO₄ required is:

How many electrons are involved in the following redox reaction?
\(\begin{align}C{{r}_{2}}O_{7}^{{2-}}+F{{e}^{{2+}}}+{{C}_{2}}O_{4}^{{2-}}\to C{{r}^{{3+}}}+F{{e}^{{3+}}}+C{{O}_{2}}(Unbalanced)\end{align}\)

\(\begin{align}XN{{a}_{2}}HAs{{O}_{3}}\text{ }+\text{ }YNaBr{{O}_{3}}\text{ }+\text{ }ZHCl\text{ }\to ~NaBr\text{ }+\text{ }{{H}_{3}}As{{O}_{4}}\text{ }+\text{ }NaCl\end{align}\)
The values of X, Y and Z in the above redox reaction are respectively:

In the following balanced reaction, \(\begin{align}XMnO_{4}^{-}+Y{{C}_{2}}O_{4}^{{2-}}+Z{{H}^{+}}\rightleftharpoons XM{{n}^{{2+}}}+2YC{{O}_{2}}+\frac{Z}{2}{{H}_{2}}O\end{align}\)
values of X, Y and Z respectively are

Given:
\(\begin{align}C{{o}^{{3+}}}+{{e}^{-}}\to C{{o}^{{2+}}};\text{ }{{E}^{o}}=+1.81V\end{align}\)
\(\begin{align}P{{b}^{{4+}}}+2{{e}^{-}}\to P{{b}^{{2+}}};\text{ }{{E}^{o}}=+1.67\text{ }V\end{align}\)
\(\begin{align}C{{e}^{{4+}}}+{{e}^{-}}\to C{{e}^{{3+}}};{{E}^{o}}=+1.61V~\end{align}\)
\(\begin{align}B{{i}^{{3+}}}+3{{e}^{-}}\to Bi;{{E}^{o}}=+0.20V\end{align}\)
oxidizing power of the species will increase in the order:

Given that \(\begin{align}E_{{{{O}_{2}}/{{H}_{2}}O}}^{o}=+1.23V\end{align}\);
\(\begin{align}E_{{{{S}_{2}}O_{8}^{{2-}}/SO_{4}^{{2-}}}}^{o}=2.05V\end{align}\)
\(\begin{align}E_{{B{{r}_{2}}/Br}}^{o}=+1.09V\end{align}\)
\(\begin{align}E_{{A{{u}^{{3+}}}/Au}}^{o}=+1.4V\end{align}\)
The strongest oxidising agent is:

Consider the following reduction processes:
\(\begin{align}C{{a}^{{2+}}}+2{{e}^{-}}\to C{{a}_{{\left( s \right)}}};\text{ }E{}^\circ =-2.87V\end{align}\)
\(\begin{align}M{{g}^{{2+}}}+2{{e}^{-}}\to M{{g}_{{\left( s \right)}}};\text{ }E{}^\circ =-2.36V\end{align}\)
\(\begin{align}N{{i}^{{2+}}}+2{{e}^{-}}\to N{{i}_{{\left( s \right)}}};E{}^\circ =-0.25V\end{align}\)
The reducing power of the metals increases in the order:

In the reaction of oxalate with permanganate in acidic medium, the number of electrons involved in producing one molecule of \(\begin{align}C{{O}_{2}}\end{align}\) is:

In which of the following reactions, hydrogen peroxide acts as an oxidizing agent?

Consider the reaction:
\(\begin{align}{{H}_{2}}S{{O}_{3}}\left( {aq} \right)\text{+}S{{n}^{{4+}}}\left( {aq} \right)+{{H}_{2}}O\left( l \right)\to ~S{{n}^{{2+}}}\left( {aq} \right)+HSO_{4}^{-}\left( {aq} \right)+3{{H}^{+}}(aq)\end{align}\)
Which of the following statements is correct?

Which one of the following cannot function as an oxidising agent?