Reduction reaction


What is reduction reaction?

Reduction reaction is a type of chemical reaction where the reactant receives one or more electrons. The reactant receiving electrons is said to be reduced. A reduction is the opposite of an oxidation  and these two reactions always occur concurrently in a so-called reduction oxidation reaction, often called a redox reaction. Because in practice, an oxidation reaction always occurs in conjunction with a reduction reaction and no electrons are available as reactants or products. If you write down only the reduction part, it will be necessary to indicate the electrons as reactants.  Below is a reaction in which a dichloromic molecule is Cl2 reduced to two chloride ions Cl‾.

Cl+ 2e‾ → 2Cl‾

Note that as the electrons are negatively charged, the two ions formation also gets a negative charge and therefore the rule of charge retention is met. Whether an element can absorb one, two or more electrons, and thus which ions it may form, depends on the location of the element in the periodic table. The reaction also shows that as a result of the electron capture the element has a lower oxidation rate. It is therefore a general rule in the case of redox reactions when an oxidation number of a reactant is lowered in the reaction, the reactant is reduced and vice versa with the oxidation. Therefore, the following reaction is also a reduction reaction, although the reactant does not get a negative charge, reducing the oxidation rate.

Zn2+  +  2e‾  →  Zn

There is a motto for reductions and oxidations which is ‘OIL RIG’, stands for ‘Oxidation Is Loss, Reduction Is Gain’. In both cases, the electrons are indirectly spoken.

In organic chemistry, a reduction is referred to as a reaction in which the number of hydrogen atoms increases or the number of bonds to oxygen atoms decreases. Therefore, it is said that a carboxylic acid is reduced to an aldehyde which is then reduced to an alcohol.


Similarly, a triple bond can be reduced to a double bond, which in turn can be reduced to single bond. Reduction of single bonds causes the linkage to be split into two, which was the case in the first reaction with dichloride. In addition, the type of reactions below are defined as addition reactions; the dihydrogen being  added / added to the molecule in each step.