Reactivity Series And Extraction Of Metals

Question 1

Metal oxides

Answer 1

Product of when metals react with oxygen, oxidation reactions as metals gain oxygen

Question 2

Oxidation

Answer 2

Metal gains oxygen but loses electrons, formation of metal ore

Question 3

Reduction

Answer 3

Metal loses oxygen but gains electrons, extraction of metal

Question 4

Displacement

Answer 4

When more reactive metal displaces less reactive metal from compound, metal ion gains electrons + is reduced, but metal atom loses electrons + is oxidised

Question 5

Corrosion

Answer 5

Destruction of materials by chemical reactions with substances in environment e.g rusting, both air + water are necessary for iron to rust

Question 6

Phytomining

Answer 6

Uses plants to absorb metal compounds which are then harvested + burned to produce ash, which contains metal compounds

Question 7

Bioleaching

Answer 7

Uses bacteria to produce leachate solutions, which contain metal compounds

Question 8

Reactivity series

Answer 8

Potassium, Sodium, Lithium, Calcium, Magnesium, (Carbon), Zinc, Iron, (Hydrogen) + Copper can be put in order of their reactivity from their reactions with water + dilute acids, reactivity of metal is related to its tendency to form positive ions, Potassium to Magnesium are extracted by electrolysis, but Carbon to Copper is extracted by reduction using carbon

Reactions of metals with water + acids limited to room temperature + don’t include reactions with steam

Question 9

Prevention of corrosion methods

Answer 9

By applying coating that acts as barrier e.g greasing, painting or electroplating, aluminium has oxide coating that protects it from further corrosion, some coatings are reactive + contain more reactive metal to provide sacrificial protection e.g zinc is used to galvanise iron

Question 10

Extraction of metals

Answer 10

Unreactive metals e.g gold are found in Earth as metal itself but most metals are found as compounds that require chemical reactions to extract metal, metals less reactive than carbon can be extracted from their oxides by reduction with carbon

Question 11

Alternate methods of extracting metals

Answer 11

Phytomining + Bioleaching avoid traditional mining methods of digging, moving + disposing of large amounts of rock

Metal compounds produced by phytomining + bioleaching can be processed to obtain metal e.g copper can be obtained from solutions of copper compounds by displacement using scrap iron or by electrolysis