Question

How to balance a reaction taking place in basic medium by ion electron method? Explain.

Answer 1

There are the following steps used to balance a reaction taking place is basic medium by ion electron method.
Step $I$: Write skeletal equation and indicate the oxidation number of all the elements.
Step $II$: Find out the species which are oxidised and which are reduced.
Step $III$: Spit the equation in two half reactions i.e., oxidation half reaction and reduction half reaction.
Step $IV$: Balance the two half reactions separately by using following step:
$\bullet$ First of all, balance the atoms of the elements which have undergone a change in oxidation number.
$\bullet$ Add electrons to whatever side necessary to make up the difference in oxidation number in each half reaction.
$\bullet$ Balance change by adding $O{H}^{-}$.
$\bullet$ Balance oxygen atoms by adding required number of $H_{2}O$ molecules to the side deficient in $O$ atoms.
$\bullet H$ atoms are balanced by adding $H_{2}O$ molecules equal in number to the deficiency of $H$ atoms and number of $O{H}^{-}$ ions are included in opposite side if the equation.
Step $V$: The two half reactions are multiplied by suitable integers to balance the number of electrons. The half reaction, are then added up.