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

${\mathrm{H}}_2 \mathrm{S}$ ($5$ moles) reacts completely with acidified aqueous potassium permanganate solution. In this reaction, the number of moles of water produced is $\mathbf{x}$, and the number of moles of electrons involved is $\mathbf{y}$. The value of $(\mathrm{x}+\mathrm{y})$ is

After balancing equation ${\mathrm{C}}_2{\mathrm{O}}_4^{2-}+{\mathrm{H}}^{+}+{\mathrm{MnO}}_4^{-}\to {\mathrm{CO}}_2+{\mathrm{Mn}}^{2+}+{\mathrm{H}}_2\mathrm{O},$ the coefficient of ${\mathrm{CO}}_2$ is (when all the coefficients are whole numbers.)

The values of $\mathrm{x}$ and $\mathrm{y}$ in the following redox reaction,
$\mathrm{x} {\mathrm{Cl}}_2+6 {\mathrm{OH}}^{-}\to {\mathrm{ClO}}_3^{-}+\mathrm{y} {\mathrm{Cl}}^{-}+3 {\mathrm{H}}_2\mathrm{O}$ are

Balance the following equations by ion electron method.

$\mathrm{Zn}+{{\mathrm{NO}}_3}^{-}\to {\mathrm{Zn}}^{2+}+\mathrm{NO}$

When a hypo solution is added to a ${\mathrm{KMnO}}_4$ solution,

The number of moles of ferrous oxalate oxidized by one mole of ${\mathrm{KMnO}}_4$ in an acidic medium is

In the chemical change:
$a{\mathrm{N}}_2{\mathrm{H}}_4+b{\mathrm{BrO}}_3^{-}⟶a{\mathrm{N}}_2+b{\mathrm{Br}}^{-}+6{\mathrm{H}}_2\mathrm{O},$ answer the following question:

What are the values of $\mathrm{a}$ and $\mathrm{b}$ in the reaction respectively:

${\mathrm{aN}}_2{\mathrm{H}}_4+{{\mathrm{bBrO}}_3}^{-}\to 3{\mathrm{N}}_2+2{\mathrm{Br}}^{-}+6{\mathrm{H}}_2\mathrm{O}$

For the following reaction :  ${\mathrm{x}\mathrm{N}\mathrm{H}}_3+\mathrm{y}\mathrm{C}\mathrm{u}\mathrm{O}\stackrel{}{\to }{\mathrm{a}\mathrm{N}}_2+\mathrm{b}\mathrm{C}\mathrm{u}+{\mathrm{c}\mathrm{H}}_2\mathrm{O}\mathrm{ }$

Determine the values of $\mathrm{x}$ and $\mathrm{y}$ respectively.

$\mathrm{x},\mathrm{y},\mathrm{z}$ in the following given redox reactions are: 

${\mathrm{xI}}^{–}+\mathrm{y}\mathrm{ }{\mathrm{IO}}_3^{–}\mathrm{ }+{\mathrm{zH}}^{+}\to {\mathrm{aI}}_2+{\mathrm{bH}}_2\mathrm{O}$

What will be the ratio of number of moles of cerric ammonium sulphate required per mole of ferrous ammonium sulphate to the number of moles of ${\mathrm{K}\mathrm{M}\mathrm{n}\mathrm{O}}_4$ required per mole of ferrous ammonium sulphate?(Cerric ammonium sulphate and potassium permanganate are used as oxidising agents in acidic medium for oxidation of ferrous ammonium sulphate to ferric sulpahte.)

What is the value of $\frac{\mathrm{p}}{\mathrm{q}}$ in the given balanced reaction?
${\mathrm{pI}}^{-}+{\mathrm{MnO}}_4^{-}+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{I}}_2+{\mathrm{MnO}}_2+{\mathrm{qOH}}^{-}$

The number of moles of ferrous oxalate required for reduction of $2/5$ moles of ${\mathrm{KMnO}}_4$ in acidic medium is:

When ${\mathrm{KMnO}}_4$ reacts with oxalic acid and $\mathrm{HCl}$ separately in acidic medium, Then ${\mathrm{KMnO}}_4$ is convert into ${\mathrm{Mn}}^{2+}, {\mathrm{C}}_2{{\mathrm{O}}_4}^{-2}$ into ${\mathrm{CO}}_2$ and ${\mathrm{Cl}}^{-}$ into ${\mathrm{Cl}}_2$. The mole ratio of $\left[{{\mathrm{MnO}}_4}^{-} : {\mathrm{C}}_2{{\mathrm{O}}_4}^{-2}\right]$ and $\left[{{\mathrm{MnO}}_4}^{-}:\mathrm{HCl}\right]$ are respective in balanced chemical equations is.

Consider the following reaction: 

${\mathrm{P}}_4\stackrel{{\mathrm{OH}}^{-}}{⟶}{\mathrm{PH}}_3+{\mathrm{H}}_2{\mathrm{PO}}_2^{-}$

Calculate the moles of hypophosphite ion produced from $10 \mathrm{moles}$ of phosphorous.

The following redox reaction takes place In acidic medium

$\mathrm{Zn}+$${{\mathrm{NO}}_3}^{-} + \mathrm{HCl}$$\to$${\mathrm{Zn}}^{2+}+{\mathrm{NH}}_4^{+}+{\mathrm{H}}_2\mathrm{O}$(unbalanced)

If $\mathrm{Zn}$ is present in excess, then how many moles of $\mathrm{HCl}$are required to reduce half a mole of ${\mathrm{N}\mathrm{a}\mathrm{N}\mathrm{O}}_3$ completely?

The number of electrons donated from substance(s) getting oxidized to the substance(s) getting reduced in the chemical equation for the following reaction is:

${\text{Cr}}_2{\text{O}}_7^{2-}+{\text{Fe}}^{2+}+{\text{C}}_2{\text{O}}_4^{2-}\to {\text{Cr}}^{\mathrm{3\; +}}+{\text{Fe}}^{3+}+{\text{CO}}_2$ (Unbalanced)

If $X$ millimole of $\mathrm{KIO}_{3}$ reacts completely with $Y$ millimole of $\mathrm{KI}$, then which of the following statements are correct?