Embibe Experts Solutions for Chapter: Redox Reactions, Exercise 1: Exercise 1

The oxidation number of sulphur is $+4$ in

Determine the oxidation number of iron in ${\mathrm{Na}}_2\left[\mathrm{Fe}(\mathrm{CN}{)}_5\left({\mathrm{NO}}^{+}\right)\right]$.

The metal with the highest oxidation state present in ${\mathrm{K}}_2{\mathrm{CrO}}_4, {\mathrm{NbCl}}_5$ and ${\mathrm{MnO}}_2$ is:

The number of electrons required to reduce chromium completely in ${\mathrm{Cr}}_2{{\mathrm{O}}_7}^{2-}$ to ${\mathrm{Cr}}^{3+}$ in acidic medium, is

When ${\mathrm{KMnO}}_4$ acts as an oxidising agent and ultimately forms ${\mathrm{MnO}}_4^{2-}, {\mathrm{MnO}}_2, {\mathrm{Mn}}_2{\mathrm{O}}_3$ and ${\mathrm{Mn}}^{2+},$ then determine the number of electrons transferred in each case.

In balancing the reaction, ${\mathrm{xH}}_2\mathrm{S}+2{\mathrm{NaNO}}_3+2\mathrm{HCl}\to \mathrm{y} \mathrm{S}+\mathrm{zNO}+\mathrm{kNaCl}+4{\mathrm{H}}_2\mathrm{O}$, one would get $\mathrm{x}, \mathrm{y}, \mathrm{z}$ and $\mathrm{K},$ respectively, as

The reaction, ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7+\mathrm{m} {\mathrm{FeSO}}_4+\mathrm{n} {\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{Cr}}_2{\left({\mathrm{SO}}_4\right)}_3+\mathrm{p} {\mathrm{Fe}}_2{\left({\mathrm{SO}}_4\right)}_3+{\mathrm{K}}_2{\mathrm{SO}}_4+\mathrm{q} {\mathrm{H}}_2\mathrm{O}$ when balanced, $\mathrm{m}, \mathrm{n}, \mathrm{p},$ and $\mathrm{q}$ are, respectively:

${\mathrm{CN}}^{-}$ is oxidised by ${\mathrm{NO}}_3^{-}$ in the presence of an acid : ${\mathrm{aCN}}^{-}+{\mathrm{bNO}}_3^{-}+{\mathrm{cH}}^{+}⟶\left(\mathrm{a}+\mathrm{b}\right)\mathrm{NO}+{\mathrm{aCO}}_2+\frac{\mathrm{c}}{2}{\mathrm{H}}_2\mathrm{O}$. What are the whole number values of $\mathrm{a}, \mathrm{b}, \mathrm{c}$ in that order?