Reducing Agents- Definition and Meaning
A reducing agent is one of the reactants of an oxidation-reduction reactions which reduces the other reactant by giving out electrons to the reactant. If the reducing agent does not passes electrons to other substance in an reaction, then the reduction process cannot occur.
Definition– “The substance which loses electrons to the other substance and gets oxidized to the higher valency state is known as reducing agent.”
The reducing agents give away electrons. The metals of the s-block in the periodic table are said to be good reducing agents. These agents have an opposite effect to measuring the agents which tend to strengthen. The reducing agent after losing electrons gets oxidized and also causes the opposite reactant to get reduced by supplying electrons. All the good reducing agents have the atoms which have low electronegativity and a good ability of atom or a molecule to attract the bonding electrons and the species having very small ionization energies. These usually serve as the good reducing agents.
All the oxidation and reduction reactions involves the transfer of electrons. When some substance is oxidized, it is said to lose electrons and the substance which receives electrons is said to be reduced. If the substance has strong tendency to lose electrons, then it is said to be strong reducing agent as it will reduce the other substances by giving electrons.
The more strong the reducing agent, the more weaker is the corresponding oxidizing agent. Fluorine gas is known to be a strong oxidizing agent and whereas F- is said to be a weak reducing agent. We also know that – the more weaker an acid then more stronger is the conjugate base. In a similar way, the more weaker the oxidizing agent then the more strong is the corresponding reducing agent as shown in the figure below.
Reducing Agent- Examples
Some of the common reducing agents includes metals such as Na, Fe, Zn, Al and non-metals such as C, S, H2. Some of the compounds and also the Hydracids such as HCl, HI, HBr, H2S behave as good reducing agents. A brief explanation over some of the reducing agents are given below-
- Lithium– Lithium is a chemical element with atomic number 3 and a symbol Li. It appears as a soft and silvery white metal and belongs to the alkali metal group of the periodic table. It is said to be a strong reducing agent when placed in solutions.
- Iodides– The salts of Iodides are said to be mild reducing agents. They react with oxygen to give out iodine. These also possess various antioxidant properties.
- Reducing sugars– Reducing sugars are those which behave in a similar as that of the reducing agents because of the free ketone group or a free aldehyde group present. All monosaccharides along with disaccharides, polysaccharides, oligosaccharides are said to be reducing sugars.
Some of the other compounds of reducing agents includes Carbon, Carbon monoxide, Ascorbic acid, Sulphur dioxide, Hydrogen, Oxalic acid, Phosphites, phosphorous acid, hypophosphites, etc.