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.
Mg → Mg2+ + 2e
Here, magneisum has oxidised by loss of electrons to form magnesium cation.
Reduction is gain of electrons.
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.
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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