Question

Explain extraction of metal in high reactivity series

Answer 1

Answer:

The metals which are very reactive usually occur in the form of their oxides, the oxides of such metals cannot be reduced by carbon. These metals are obtained by electrolytic reduction.

Example: sodium, magnesium are obtained by electrolysis of their molten chlorides. Metals are deposited at cathode and chlorine is deposited at anode.

At cathode: Na(+ve) + e(-ve) = Na

At anode: 2Cl(-ve)=Cl2 + 2e(-ve)

Aluminium is obtained by electrolytic reduction of aluminium oxides ( Al2O3)

Al2O3=2Al^3(+ve) + 3O ^2(-ve)

At cathode: Al^3(+ve) + 3e(-ve)= Al (reduced deposited)

At anode: O ^2(-ve) = O(1/2 O2) + 2e(-ve) ( oxidised)

I hope it was helpful to you...

Answer 2

Extracting metals in high reactivity series :-

The metals such as,

➟ K ( Potassium )

➟ Na ( sodium )

➟ Ca ( Calcium )

They are very reactive, and hardly found in free state. They form very strong bond with other elements.

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‣ To extract them from their ore, we use the process, Electrolysis.

( Electrolysis :- Process of breaking down of a compound by passing electricity. )

For example lets take, Sodium chloride.

‣ During electrolysis As Sodium metal has positive ions, it gets deposited at the cathode (negatively charged electrode) and Chlorine has negative, gets deposited at the anode (positively charged electrode).

Anode reaction = Cl- --> Cl2 + 2e-

Cathode reaction = Na + e- --> Na+