This document discusses various topics related to extracting and refining metals, including: 1. Metals are found naturally in different forms, with unreactive metals like gold found free and reactive metals like potassium found in compounds. 2. A reactivity series orders metals based on their reactivity, with the most reactive extracted through electrolysis and moderately reactive ones reduced using carbon or displacement reactions. 3. Impure metal ores are refined through processes like roasting or calcination to separate the metal from waste gangue before extracting the pure metal.

2. Topics
• Introduction.
• Reactivity series.
• Enrichment of ores.
• Extracting metals low,
middle,& top of series.
• Refining of metals.

3. Introduction
• Some Metals Are Found In Earth Crust In Free State
And Some In Form Of Their Compounds.
• The Metals At Bottom Of Activity Series Are Least
Reactive & Are Found In Free State. Eg:
Gold,silver,copper Ect.
• The Metals At Top Of Activity Series As( K, Na, Ca,
Mg, Al) Are Very Reactive.
• The Metals At Middle Of Activity Series As (Zn ,Fe ,Pb
, Cu) Are Moderately Reactive And Found In Crust
Mainly As Oxides, Sulphides, Or Carbonates.

4. Reactivity Series
• This Is Reactivity Series Where K,
Na, Ca, Mg &Al Are Electrolysis.
• Zn, Fe, Pb, Cu Are Reduction
Using Carbon.
• Ag, Au Are Found In Native State.
K
Na
Ca
Mg
Al
Zn
Fe
Pb
Cu
Ag
Au

5. Enrichment of ores
• Ores Mined From The Earth Are Usually
Contaminated With Large Amounts Of
Impurities Such As Soil, Sand Etc.Is Called
Gangue.
• The Processes Used For Removing The Gangue
From Ore Is Based On Differences B/W The
Physical Or Chemical Properties Of The
Gangue & The Ore.

6. Extracting metals low in series
• Metals Low In Series Are Very Unreactive.
• Oxides Of These Metals Can Be Reduced To
Metals By Heating Alone.Eg:when Cinnabar Is
Heated In Air , First It Is Converted Into
Mercuric Oxide. Then It Is Reduced To
Mercury On Further Heating.
• 2hg(s) +3o2(g)2hgo(s)+ 2so2(g)
2hgo(s)2hg +O2

7. Extracting metals from middle of
series
• Metals In Middle Of Series Are Moderately
Reactive.
• They Are Present As Sulphides & Carbonates.
• Prior To Reduction, Metal Sulphides & Carbonates
Must Be Converted Into Metal Oxides.
• When Sulphide Ores Are Converted Into Oxides By
Heating Strongly In Presence Of Excess O2 Is Known
As Roasting.
• When Carbonates Ore Is Changed In Oxides By
Heating Strongly In Limited Air Is Known As
Calcination.

8. Chemical reaction of roasting and
calcination of zinc ores
• Roasting:
• 2zns(s) +3O2 (G) 2zno(s) + 2SO2 (G)
• Calcination:
• Znco3(s)  Zno(s) + Co2(g)
• The Metal Oxides Are Then Reduced To
Corresponding Metals By Suitable Reducing
Agents As Carbon. Eg: When Zinc Oxide Is
Reduced To Metallic Zinc.
• Zno (S)+ C(s) Zn(s)+ Co(g)

9. Reduction agents
• Besides Using Carbon (Coke) To Reduce Metal
Oxides To Metal, Sometimes Displacement
Reactions Can Also Be Used In Reduction.
• The Highly Reactive Metal As Na, Ca, Al, Ect. Are
Used As Reducing Agents As They Can Displace
Metals Of Lower Resistivity From Their
Compounds.
• For Eg: When Manganese Dioxide Is Heated With
Aluminium Powder :
• 3mno2(s) + 4al(s)3mn +2al2o3(s) +Heat

10. Substances Getting Oxidized &
Reduced
• These Displacements Reactions Highly
Exothermic In Nature.
• The Amount Of Heat Produced Is So Large
That Metals Are Produced In Molten State.

11. Thermit Reaction
• The Reaction Of Iron(iii) Oxide[fe2o3 ] With
Aluminium Is Join Railway Tracks Or Cracked
Machine Parts This Is Known As Thermit
Reaction.
• The Reaction For Thermit Reaction Is:
• Fe2o3[s] + 4al[s] 3mn(i) +2al2o3(s) + Heat

12. Extracting metals from top of series
• These Metals Are Very Reactive.
• They Cannot Be Obtained By Their
Compounds While Heating By Carbon. For Eg:
Carbon Cannot Reduce The Oxide Of Sodium,
Magnesium, Calcium, Aluminium Ect. It Is
Because They Have More Affinity Of O2 Than
CO2 .

13. Extracting metals from top of series
• These Metals Are Obtained From Electrolytic
Reduction. For Eg:
• Na, Mg, Ca Are Obtained By The Electrolysis
Of Their Molten Chlorides.
• The Metals Are Deposited At The Cathode
(Negatively Charged Electrode) .And Cl Is
Liberated At Anode (Positively Charged
Cathode)

14. Refining Of Metals
• Metals Are Produced By Various Reduction
Process Which Are Not Very Pure.
• They Contain Impurities Which Must Be
Removed To Obtain Pure Metals.
• The Most Widely Used Method For Refining
Impure Metals Is Electrolytic Refining .

15. Electrolytic refining
• Many Metals Such As Cu, Zn, Sn, Ag, Au Etc
Are Refined Electrolytically.
• The Impure Metal Is Made Anode & A Thin
Strip Of Pure Metal Is Made Of Cathode .
• Solution Of Metal Salt Is Used In Electrolyte.

16. Electrolytic refining
• On Passing The Current Through The
Electrolyte, The Pure Metal From The Anode
Dissolves Into The Electrolyte.
• An Equivalent Amount Of Pure Metal From
The Electrolyte Is Deposited On The Cathode.
• The Soluble Impurities Go Into The Solution,
Whereas, The Insoluble Impurities Settle
Down At The Bottom Of The Anode And Are
Known As Anode Mud.