Embibe Experts Solutions for Chapter: Redox Reactions, Exercise 2: Exercise-2

In the following reaction:

$\mathrm{Cr}(\mathrm{OH}{)}_3+{\mathrm{OH}}^{-}+{\mathrm{IO}}_3^{-}\to {\mathrm{CrO}}_4^{2-}+{\mathrm{H}}_2\mathrm{O}+{\mathrm{I}}^{-}$

The table below gives the results of three titration carried out with $0.200 \mathrm{M} \mathrm{HCl}$. To determine the molarity of a given $\mathrm{NaOH}$ solution using phenolphthalein as indicator. $\mathrm{NaOH}$ was taken in the burette and $\mathrm{HCl}$ was taken in a conical flask for the titration.

$\begin{array}{|llll|}\hline \mathrm{TitrationNo}. & {\mathrm{V}}_{\mathrm{HCl}\left(\mathrm{mL}\right)}& {\mathrm{V}}_{\mathrm{NaOH} \left(\mathrm{mL}\right)}& {\mathrm{M}}_{\mathrm{NaOH}mold{\mathrm{m}}^{-3}}\\ \mathrm{I}& 21.4& 19.3& 0.222\\ \mathrm{II}& 18.6& 16.8& 0.221\\ \mathrm{III}& 22.2& 21.1& 0.210\\ \hline\end{array}$

The actual molarity of the prepared $\mathrm{NaOH}$ solution was $0.220 {\mathrm{moldm}}^{-3}$. Which among the following could be the reason for the wrong value obtained in titration $\mathrm{III}$?

If $25 \mathrm{mL}$ of ${\mathrm{H}}_2{\mathrm{SO}}_4$ solution reacts completely with $1.06 \mathrm{g}$ of pure ${\mathrm{Na}}_2{\mathrm{CO}}_3,$ what is the normality of this acid solution:

During the disproportionation of lodine to iodide and iodate ions, the ratio of iodate and iodide ions formed in alkaline medium is :

How many equivalents of $\mathrm{Mg}$ would have to react in order to liberate $4{ \mathrm{N}}_{\mathrm{A}}$ electrons? $\left(\mathrm{Mg}-2{\mathrm{e}}^{-}\to {\mathrm{Mg}}^{2+}\right)$

In the titration of ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ and ferrous sulphate, following data is obtained,

${\mathrm{V}}_1 \mathrm{mL}$ of ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ solution of molarity ${\mathrm{M}}_1$ requires ${\mathrm{V}}_2 \mathrm{mL}$of ${\mathrm{FeSO}}_4$ solution of molarity ${\mathrm{M}}_2.$

Which of the following relations is/are true for the above titration?

Choose the correct statement(s) :

Which of the following samples of reducing agents is /are chemically equivalent to $25 \mathrm{mL}$ of $0.2 \mathrm{N}$ ${\mathrm{KMnO}}_4$ to be reduced to ${\mathrm{Mn}}^{2+}$ and water: