What is the difference between redox reactions and oxidation and reduction reactions ?

Asked by shivamkumar3400 | 12th Jul, 2016, 07:49: PM

Expert Answer:

Oxidation is loss of electrons.
Example: 
Mg → Mg2+ + 2e
Here, magneisum has oxidised by loss of electrons to form magnesium cation.
 
Reduction is gain of electrons.
Example:
Mg2+ + 2e  → Mg 
Here, magnesium cation got reduced to magnesium metal.
 
Redox means reduction and oxidation taking place in the same reaction then it is called as redox reaction.
Example:
 
Consider the reaction between zinc metal and hydrochloric acid.

Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)

If this reaction where broken down to the ion level:

Zn(s) + 2 H+(aq) + 2 Cl-(aq) → Zn2+(aq) + 2 Cl-(aq) + 2 H2(g)

Zinc atom loses two electrons to become a Zn2+ ion so undergo oxidation, 
Hydrogen ions are gaining electrons and bonding together to form dihydrogen gas. So undergo reduction.
Hence thi reaction is redox reaction.

Answered by Prachi Sawant | 13th Jul, 2016, 10:39: AM

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