Difference Between Oxidation and Reduction

Main Difference

The main difference between oxidation and reduction is that oxidation is the increase of oxidation state, whereas reduction is the decrease of oxidation state.

Oxidation vs. Reduction

Oxidation can be well-defined as the loss of electrons from a molecule, atom or an ion whereas reduction is the gain of electrons from a molecule, atom or an ion. Oxidation is the addition of oxygen during the reaction, whereas reduction is the loss of oxygen during the reaction. Oxidation is the loss of protons during the reaction; conversely, the reduction is the gain of protons during the reaction. Oxidation is the increase of the oxidization state, whereas reduction is the decrease of oxidation state. Oxidation involves increasing the positive charge of chemical species, whereas reduction involves in negative charge of chemical species. Oxidation always occurs in reducing agents conversely reduction occur in oxidizing agents. Oxidation is a process where it releases energy, whereas reduction is a process where it stores energy. Oxidation is a process related to reducing agent on the other hand reduction is a process related to the oxidizing agent. Oxidation is the addition of an electronegative atom or an ion whereas reduction is the removal of an electronegative atom or an ion. Oxidation is the removal of an electropositive atom or an ion whereas reduction is the addition of an electropositive atom or ion. Oxidation is a process in which reactant supplies energy whereas reduction is a process in which reactant receives energy.

Comparison Chart

OxidationReduction
Oxidation is the increase of oxidation state.The reduction is the decrease in oxidizing state.
Loss or Gain of Proton
Loss of a protonThe gain of a proton
Addition or Removal of Oxygen
Addition of oxygenElimination of oxygen
Loss or Gain of Electron
Loss of electronGain of electron
Electronegative Atom or Ion
Addition of electronegative atom or ionElimination of electronegative atom or ion
Electropositive Atom or Ion
Elimination of electropositive atom or ionAddition of electropositive atom or ion
Heat Energy During the Reaction
It supplies energyIt stores energy
Oxidation State
Oxidation state increasesOxidation state decreases
Occurrence
Occur in reducing agentOccur in oxidizing agent

What is Oxidation?

Oxidation is a process in which species loses an electron or a proton. It is a process of adding oxygen. Oxidation is a process in which there is an increase of oxidation state. Oxidation always occurs where there is a reducing agent. It always supplies energy to the system. The oxidation reaction is a half-reaction. It involves an increase of positive charge or decrease of negative charge. Oxidation is an addition of an electronegative atom or an ion and removal of an electropositive atom or an ion. Formerly, the definition of oxygen was that where there is an addition of oxygen there is oxidation, but this idea can not hold much longer because there is some oxidation reaction in which there is no oxygen. From this, we can say that oxygen is not necessary for the oxidation reactions. There is also an old definition of oxidation is that it involves in the elimination of hydrogen. But this also cannot hold for all the chemical reactions. Oxidation is half process, where there is loss of an electron to the surrounding there are a chemical species which accepts this electron. It means where there is oxidation there is a reduction.

Example

Fe+2 is oxidized to Fe+3

What is Reduction?

The reduction is a process in which a specie gains an electron or a proton. It is the process of elimination of oxygen. The reduction is a process in which there is a decrease in oxidation state. Reduction always occurs where there is an oxidizing agent. It always gains energy from the system and store in itself. It always causes a decrease in positive charge and an increase in a negative charge. The reduction is the elimination of an electronegative atom or an ion and addition of an electropositive atom or an ion during the chemical reaction. The reduction is a process that is commonly used in acid-base reaction or electrochemical processes along with oxidation. Previously, it was believed that reduction means the elimination of oxygen but this old definition did not hold for a long time because there are some redox processes in which there is no oxygen is involved. It means that oxygen is not essential for the reduction. There was also an old definition in which reduction means the addition of an electron, but this is not quite acceptable for some reactions. But now new definition is most acceptable. Also, we know that reduction is half process. In redox processes where there is a reduction there will be oxidation.

Example

Mn+7 is reduced to Mn+2

Key Differences

  1. Oxidation is the cause of an increase in oxidation state, whereas reduction is the cause of decrease in oxidation state.
  2. Oxidation is the result of the loss of an electron by the reactant. On the other hand, the reduction is the result of gain of an electron by the reactant.
  3. Oxidation is the result of the loss of proton by the reactant: conversely, the reduction is the result of the gain of proton by the reactant.
  4. Oxidation causes an increase in positive charge, whereas reduction causes a decrease in positive charge.
  5. Oxidation occurs where there is a reducing agent; on the other hand, the reduction occurs where there is an oxidizing agent.
  6. Oxidation is the addition of oxygen, whereas reduction is the elimination of oxygen.
  7. Oxidation is the addition of an electronegative atom or an ion conversely reduction is the addition of an electropositive atom or an ion.

Conclusion

Above discussion concludes that oxidation and reduction are the two half-reactions of a complete redox reaction. The basic difference is that oxidation results in increasing the oxidation state; on the other hand, reduction results in decreasing the oxidation state.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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