MCQ Detailed View

Oxidation is a fundamental chemical process that occurs during many reactions, especially those involving metals, non-metals, and compounds that can transfer electrons. In chemistry, oxidation is defined as the loss of electrons by an atom, ion, or molecule during a chemical reaction. When a substance loses electrons, its oxidation state increases, meaning it becomes more positively charged.

A simple example of oxidation is the reaction of sodium with chlorine to form sodium chloride (NaCl). In this reaction, sodium loses one electron to chlorine, making sodium oxidized while chlorine is reduced by gaining an electron. This process is part of a broader concept known as redox reactions (oxidation-reduction reactions), where one substance is oxidized and another is reduced simultaneously.

Oxidation does not involve gaining electrons, protons, or losing protons. The loss of electrons is the key event that defines oxidation. For instance:

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  Iron rusting: Iron atoms lose electrons to oxygen in the presence of water, forming iron oxide (rust).

  
  


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  Combustion reactions: Fuels lose electrons when reacting with oxygen, releasing energy in the process.

  
  

In earlier chemistry definitions, oxidation was thought to mean simply “adding oxygen to a substance.” While that is often true, the modern definition based on electron transfer is more accurate and applies to many reactions beyond oxygen involvement.Understanding oxidation is important because it explains how batteries work, how metals corrode, how biological respiration releases energy, and how industrial processes like metal extraction occur. Oxidation is one-half of every redox reaction, with the other half being reduction (gain of electrons).

In summary, oxidation always refers to the loss of electrons during a chemical reaction, making this the correct answer for this question.