Describe the extraction of zinc from ore

Explanation:

The chief Ore of zinc is zinc blende.

The extraction of zinc from zinc blende involves the following steps.

Concentration: The ore is crushed and then concentrated by froth-floatation Process.

Roasting: The concentrated ore is then roasted in the presence of excess of air at about 1200k:

2ZnS+3O2 → Δ2ZnO+2SO2

​

Reduction: Zinc oxide is mixed with powdered coke and heated to 1673k in a fire clay retort in which ZnO is reduced to zinc metal.

ZnO+C → Zn+CO

Purification: Zinc is purified by electrolytic refining. In this process, impure zinc is anode and cathode is of pure thin sheet of zinc. The electrolyte is ZZnSO solution containing a little of dil.H2SO4.

On passing electric current pure zinc gets deposited at the cathode.

35 KJ.

Explanation:

The activation energy is the minimum energy that must be overcome for a reaction to take place.

In the diagram given above, the activation energy lies between the energy of the reactants and that at the peak.

Thus we can calculate the activation energy as follow:

Energy of reactants = 30 KJ

Energy at the peak = 65 KJ

Activation energy =..?

Activation energy = Energy at the peak – Energy of reactants

Activation energy = 65 – 30

Activation energy = 35 KJ

Therefore, the activation energy of th reaction is 35 KJ