Question

What happens in oxidation reduction reactions?

Answer 1

Hint: As we know, an oxidation reduction reaction (Also known as redox reaction) is a reaction which involves the transfer of electrons between chemical species like atoms, ions, or molecules that participates in the reaction. So in this question we are asked to explain about oxidation and reduction reactions.

Complete answer:
Let us discuss about the oxidation-reduction reaction followed by few examples of it:-
-An oxidation reduction (also known as redox) reaction is a type of chemical reaction which involves a transfer of electrons between two species. It is any chemical reaction in which the oxidation number of a chemical species such as molecule, atom, or ion changes by losing or gaining an electron.
-Redox reactions are most common and important in some of the basic functions of life which includes processes like photosynthesis, respiration, combustion and corrosion or rusting.
-During a oxidation reduction reaction, some chemical species undergo oxidation or can say the loss of electrons, while others undergo reduction or can say the gain of electrons.
-Let us consider the reaction between iron and oxygen to form rust so as to explain this reaction:-
$4Fe(s)+3{{O}_{2}}(g)\to 2F{{e}_{2}}{{O}_{3}}(s)$
Oxidation state of atoms before and after the reaction:-

Before reaction	After reaction
Fe = 0	Fe = +2
O = 0	O = -2

As we can see that in this reaction, neutral iron (Fe) loses electrons to form $F{{e}^{2+}}$ions and neutral oxygen (O) gains electrons to form ${{O}^{2-}}$ions. In other words we can say that iron got oxidized and oxygen got reduced.

Note:
-Primarily, oxidation was also defined as the gain of oxygen atoms or loss of hydrogen atoms whereas reduction was defined as the gain of hydrogen atoms and loss of oxygen atoms.
-Also many reactions in organic chemistry are redox reactions because of the changes in oxidation states, without distinct electron transfer.