Question

how can we harness redox reactions?

Answer 1

Answer:

A redox reaction is a type of reactions that involved the electron transfers between two species (oxidizing agent and reducing agent).

E.g Fe₂O₃ + 2Al => Al₂O₃ + 2Fe

Oxidizing agent = Which it self get reduced and oxidized the other species in the chemical reaction (like Fe) in above example

Reducing agent = Which it self get oxidized by reducing the other species present in the chemical reactions (like Al) in the above example

The transfer of electrons from one species to other species (or more specifically from one region to other region) results in the formation of electrical current. So, to harness the redox reaction, we can separate the oxidizing and reducing species and the chemical process (redox reaction) is controlled by providing the medium which allow the movement of electrons transfer such as an external wire.

In this way, we can control the redox reaction and electrical energy can be harnessed from the chemical reaction happening.

The most common example for such kind of reaction is batteries. In batteries, the non-spontaneous process is driven by the external applied voltage and spontaneous process results in a chemical reaction which generates the electrical current by the migration of electrons from one electrode to another electrode.

example:

Galvanic cell or voltaic cell

In which,  the following reaction (spontaneous) happens;

Zn + Cu²⁺ → Zn²⁺ + Cu

And many more examples are presents

Such as Concentration cells (the different gradients of concentration drives the chemical reaction), Electrolytic cell (driving the non-spontaneous redox reactions by external voltage) etc.

Please let me know, if you need more help on the same by commenting below the answer.

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