Metals Extraction and Properties Lecture Notes

Vocabulary-style flashcards covering the ores, extraction processes, chemical reactions, and industrial uses of Sodium, Aluminium, Zinc, Iron, Lead, and Copper based on metallurgy lecture notes.

Metallurgy

The science and technology of extracting metals from their ores.

Ore

A mineral deposit with a reasonable composition of a desired metal from which a metal can be obtained on a commercial scale.

Gangue

The earthly material or impurities found together with minerals in an ore.

Concentration

The process of increasing the percentage of mineral compound in the ore by removing impurities based on differences in properties.

Froth Floatation

A concentration method mainly used for sulphide ores where oiled ore particles attach to air bubbles and float as froth while impurities sink.

Chemical Leaching

A process where a crushed ore is dissolved in a chemical that only dissolves the ore, allowing it to be separated from insoluble impurities.

Bayer's Process

The chemical concentration method used to purify Bauxite by taking advantage of the amphoteric nature of aluminium oxide.

Magnetic Separation

A method used to separate magnetic components from non-magnetic materials, utilized for ores like Magnetite ($Fe_3O_4$) and Chromite.

Optical Sorting

A manual technique for separating ore particles by physical hand picking based on color differences detectable by the naked eye.

Hydraulic Washing

A concentration method that utilizes the difference in density to wash away lighter earthly materials while denser ore particles sink to the bottom.

Electrolytic Method

The extraction process used for highly reactive metals like Sodium, Potassium, Calcium, Magnesium, and Aluminium which occur in very stable ores.

Down's Process

The electrolytic process used to extract Sodium from fused or molten Sodium chloride in a specialized cell.

Down's Cell Electrolyte

Molten Sodium chloride with $CaCl_2$ added to lower the melting point from $800\,^{\circ}\text{C}$ to $600\,^{\circ}\text{C}$.

Down's Cell Anode Reaction

$$2Cl^- \rightarrow Cl_2 + 2e^-$$

Down's Cell Cathode Reaction

$$Na^+ + e^- \rightarrow Na$$

Sodium Vapour Lamps

Street lighting that produces a yellow light preferred for its ability to penetrate fog better than white light.

Aluminium Chief Ore

Bauxite ($Al_2O_3\cdot 2H_2O$).

Cryolite ($Na_3AlF_6$)

A substance added to purified Bauxite (alumina) to lower its melting point from $2015\,^{\circ}\text{C}$ to between $800\,^{\circ}\text{C}$ and $1000\,^{\circ}\text{C}$ during electrolysis.

Hall's Cell

The electrolytic cell used for the extraction of Aluminium using carbon/graphite electrodes.

Aluminium Anode Reaction

$$2O^{2-} \rightarrow O_2 + 4e^-$$

Aluminium Cathode Reaction

$$Al^{3+} + 3e^- \rightarrow Al$$

Duralumin

An alloy of Aluminium, copper, Manganese, and Magnesium that is harder and has higher tensile strength than pure Aluminium.

Malleability

The ability of metals to be hammered into sheets.

Ductility

The ability of a metal to be rolled into wires.

Zinc Chief Ore

Zinc blende ($ZnS$) or Calamine ($ZnCO_3$).

Zinc Roasting Equation (Sulphide)

$$2ZnS + 3O_2 \rightarrow 2ZnO + 2SO_2$$

Galvanization

The process of coating iron sheets with zinc to prevent rusting.

Iron Chief Ore

Haematite ($Fe_2O_3$) and Siderite ($FeCO_3$).

Blast Furnace Charge

The mixture of Iron Ore, Coke, and Limestone loaded into the top of the furnace.

Main Iron Reducing Agent

Carbon (II) Oxide gas ($CO$).

Iron Reduction Equation (Main)

$$Fe_2O_3 + 3CO \rightarrow 2Fe + 3CO_2$$

Slag (Iron Extraction)

Molten Calcium Silicate ($CaSiO_3$) formed by the reaction of Calcium oxide and Silica impurities, which floats on the molten iron and protects it from re-oxidation.

Pig Iron

The 90-95% pure iron obtained directly from the Blast furnace, containing carbon as the main impurity.

Mild Steel

An alloy containing about 0.3% Carbon and 99.7% Iron used for making car bodies and railway lines.

Stainless Steel

An alloy containing 74% Iron, 18% Chromium, and 8% Nickel used for cutlery and sinks.

Lead Chief Ore

Galena ($PbS$).

Imperial Smelting Furnace

The furnace used for the reduction of Lead (II) Oxide using coke and carbon (II) oxide.

Lead Roasting Equation

$$2PbS + 3O_2 \rightarrow 2PbO + 2SO_2$$

Solder

An alloy of lead used in joining metals.

Copper Chief Ore

Copper pyrites ($CuFeS_2$).

Blister Copper

The 97.5% pure copper obtained after the reduction of copper (I) oxide by unreacted copper (I) sulphide.

Copper Electro-refining Electrolyte

A solution of dilute copper (II) sulphate ($CuSO_4$).

Copper Anode Reaction (Purification)

$$Cu_{(s)} \rightarrow Cu^{2+}_{(aq)} + 2e^-$$

Copper Cathode Reaction (Purification)

$$Cu^{2+}_{(aq)} + 2e^- \rightarrow Cu_{(s)}$$

Brass

An alloy of copper and zinc.

Bronze

An alloy of copper and tin.

German Silver

An alloy of Copper, Zinc, and Silver used for electroplating.