Question

Write a balanced overall reaction from these unbalanced half-reactions.

In---->In^3+

Cd^2+ ---->Cd

Answer 1

Concepts and reason

Write the given unbalanced reactions in two half reactions separately.

Balance the electrons. Add the two half reactions to get the final balanced reaction.

Fundamentals

A balanced equation is an equation which contains all the reactants and products in a fixed ratio. A balanced equation has the following characteristics:

1)It should follow the law of conservation of mass.

2)The total number of different types of elements on reactant side should be equal to the product side.

3)Stoichiometric coefficients are put in front of the molecules on both the reactant and product side to balance a given reaction. The coefficients to be used are whole number or fractional number.

The half reactions are written as follows:

${\rm{In}} \to {\rm{I}}{{\rm{n}}^{ + 3}}$

${\rm{C}}{{\rm{d}}^{ + 2}} \to {\rm{Cd}}$

On writing the electrons, the reactions obtained are as follows:

${\rm{In}} \to {\rm{I}}{{\rm{n}}^{ + 3}} + 3{{\rm{e}}^ - }$

${\rm{C}}{{\rm{d}}^{ + 2}} + 2{{\rm{e}}^ - } \to {\rm{Cd}}$

On balancing the electrons, the reactions obtained are as follows:

${\rm{2In}} \to 2{\rm{I}}{{\rm{n}}^{ + 3}} + 6{{\rm{e}}^ - }$

${\rm{3C}}{{\rm{d}}^{ + 2}} + 6{{\rm{e}}^ - } \to 3{\rm{Cd}}$

The balanced reaction is written as follows:

${\rm{2In}} + {\rm{3C}}{{\rm{d}}^{ + 2}} \to 2{\rm{I}}{{\rm{n}}^{ + 3}} + 3{\rm{Cd}}$

Ans:

The balanced reaction is as follows:

${\rm{2In}} + {\rm{3C}}{{\rm{d}}^{ + 2}} \to 2{\rm{I}}{{\rm{n}}^{ + 3}} + 3{\rm{Cd}}$