Question

How do you determine which element oxidized in a reaction?

Answer 1

Hint: The answer here is based on the concept of oxidation where the change in the oxidation number of an element will give you which element is oxidized. Write down an example to know this.

Complete step by step answer:
In the lower classes of chemistry, we have dealt with the concepts of oxidation, reduction and also about the oxidation state of the atoms in a compound and the changes in the oxidation numbers and many other concepts.
Let us now see how we can know about which element is oxidized in a reaction by taking a simple example.
- Oxidation number is a charge possessed by an atom within the molecules and this gives information about electron transfer.
- An atom is said to be oxidized when it loses an electron and an atom is said to be reduced when it gains electrons.
- For a simple combustion reaction:
\[C{{H}_{4}}+2{{O}_{2}}\to C{{O}_{2}}+2{{H}_{2}}O\]
- The oxidation number of carbon in methane is -4 and that of hydrogen is +1 and oxygen is 0 and this is because oxygen neither donated nor accepted electrons.
- The carbon is oxidized up to +4 in carbon dioxide gas and the oxygen is reduced to -2 in water on the product side.
- Thus, there are several examples which depict the oxidation and reduction of an atom within the molecule.

Note: Note that oxidation numbers represent the potential charge of an atom in its ionic state. The reaction where the oxidation and reduction takes place in the same reaction is called as the redox reaction.