Balancing of Redox Reactions

Which of the following reactions are balanced

(i) ${\mathrm{Cr}}_2{\mathrm{O}}_{7\left(\mathrm{aq}\right)}^{2-}+3{\mathrm{H}}_2{\mathrm{S}}_{\left(\mathrm{g}\right)} +8{\mathrm{H}}_{\left(\mathrm{aq}\right)}^{+}\to 2{\mathrm{Cr}}_{\left(\mathrm{aq}\right)}^{3+}+3{\mathrm{S}}_{\left(\mathrm{s}\right)}+7{\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{l}\right)}$

(ii)  $2{{\mathrm{Cu}}^{2+}}_{\left(\mathrm{aq}\right)}+4{\mathrm{I}}^{-}{\text{}}_{\left(\mathrm{aq}\right)}\to {\mathrm{Cu}}_2{\mathrm{I}}_2{}_{\text{(}\mathrm{s})}+{\mathrm{I}}_2{}_{\left(\mathrm{g}\right)}$

Which of the following chemical equations are balanced:

 (i)  $2{\mathrm{MnO}}_4^{-}\left(\mathrm{aq}\right)+5{\mathrm{C}}_2{\mathrm{O}}_4^{2-}\left(\mathrm{aq}\right)+16{\mathrm{H}}^{+}\left(\mathrm{aq}\right)\to 2{\mathrm{Mn}}^{2+}\left(\mathrm{aq}\right)+8{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+10{\mathrm{CO}}_2\left(\mathrm{g}\right)$

(ii)  ${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}\left(\mathrm{aq}\right)+6{\mathrm{Fe}}^{2+}\left(\mathrm{aq}\right)+14\text{}{\mathrm{H}}^{+}\left(\mathrm{aq}\right)\to 2\text{}{\mathrm{Cr}}^{3+}\left(\mathrm{aq}\right)+6{\mathrm{Fe}}^{3+}\left(\mathrm{aq}\right)+7{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

On balancing the given redox reaction

$\mathrm{a} {\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}+{\mathrm{bSO}}_3^{2-}\left(\mathrm{aq}\right)+{\mathrm{cH}}^{+}\left(\mathrm{aq}\right)\stackrel{}{\to }2{\mathrm{aCr}}^{3+}\left(\mathrm{aq}\right)+{\mathrm{bSO}}_4^{2-}\left(\mathrm{aq}\right)+\frac{\mathrm{c}}{2}{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

The coefficients $\mathrm{a},\mathrm{b},\mathrm{c}$are found to be respectively

${\mathrm{KMnO}}_4$ is titrated with ferrous ammonium sulphate hexahydrate in presence of dilute ${\mathrm{H}}_2{\mathrm{SO}}_4.$ Number of water molecules produced for $2$ molecules of ${\mathrm{KMnO}}_4$ is $\_\_\_\_\_\_\_$

See the following chemical reaction:

${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}+{\mathrm{XH}}^{+}+6{\mathrm{Fe}}^{2+}\to {\mathrm{YCr}}^{3+}+6{\mathrm{Fe}}^{3+}+{\mathrm{ZH}}_2\mathrm{O}$

The sum of X, Y and Z is

$2{\mathrm{IO}}_3^{-}+{\mathrm{xI}}^{-}+12{\mathrm{H}}^{+}\to 6{\mathrm{I}}_2+6{\mathrm{H}}_2$   What is the value of $\mathrm{x}$?

Consider the reaction

${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}+{\mathrm{xH}}^{+}+{\mathrm{Fe}}^{2+}\stackrel{}{\to }{\mathrm{yFe}}^{3+}+2{\mathrm{Cr}}^{3+}+{\mathrm{zH}}_2\mathrm{O}$

Sum of $\mathrm{x},\mathrm{y} \mathrm{and} \mathrm{z}$ are

Write down the balanced chemical equation for the reaction of ${\mathrm{H}}_2\mathrm{S}$ with aqueous solution of ${\mathrm{SO}}_2$ and write the roles (oxidant/reductant) of the reactants in the reaction.

Explain Half Reaction Method briefly with rules and give an example?

Balance the following redox reaction by ion-electron method:
${\mathrm{Cr}}_2{{\mathrm{O}}_7}^{2-}\left(\mathrm{aq}\right)+{\mathrm{SO}}_2\left(\mathrm{g}\right)\to {\mathrm{Cr}}^{3+}\left(\mathrm{aq}\right)+{{\mathrm{SO}}_4}^{2-}\left(\mathrm{aq}\right) (\mathrm{acidic} \mathrm{medium})$

Balance the following redox reaction by half reaction method
${\mathrm{Fe}}^{2+}\left(\mathrm{aq}\right)+{\mathrm{Cr}}_2{{\mathrm{O}}_7}^{2-}\left(\mathrm{aq}\right)\to {\mathrm{Fe}}^{3+}\left(\mathrm{aq}\right)+{\mathrm{Cr}}^{+3}\left(\mathrm{aq}\right) (\mathrm{acid} \mathrm{medium})$

${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7+\mathrm{HCl}---->\mathrm{xKCl}+{\mathrm{yCrCl}}_3+{\mathrm{zCl}}_2+{\mathrm{wH}}_2\mathrm{O}$
Then the value of $\mathrm{x}+\mathrm{y}+\mathrm{z}$is........

Consider the given reaction as balanced equation in acidic medium

$\mathrm{aCr}{\left(\mathrm{OH}\right)}_3+{\mathrm{blO}}_3^{-}+{\mathrm{cOH}}^{-}\to {\mathrm{dl}}^{-}+{\mathrm{aCrO}}_4^{2-}+{\mathrm{eH}}_2\mathrm{O}$

The ratio of $\mathrm{b}$ to $\mathrm{a}$ is:

Which of the following is not a redox change?

In the redox reaction

$\mathrm{x} \mathrm{MnO} + \mathrm{y} {\mathrm{PbO}}_2 + \mathrm{z} {\mathrm{HNO}}_3\stackrel{}{\to }{\mathrm{HMnO}}_4+\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2+{\mathrm{H}}_2\mathrm{O}$

What are $\mathrm{x}$ and $\mathrm{y}$ in the following reaction?

$\mathrm{x} {\mathrm{Pb}}_3{\mathrm{O}}_4\to \mathrm{yPbO}+{\mathrm{O}}_2$

How to balance a redox reaction by the oxidation number method?

When white phosphorus $\left({\mathrm{P}}_4\right)$ is boiled in alkaline medium, it disproportionates as

${\mathrm{P}}_4 + \mathrm{NaOH} \to {\mathrm{PH}}_3 + {\mathrm{NaH}}_2{\mathrm{PO}}_2$

In the above redox reaction, ${\mathrm{NaH}}_2{\mathrm{PO}}_2$ and ${\mathrm{PH}}_3$ are produced in the molar ratio of