Railway Science (Chemistry-Metallurgy)

Ore is a deposit of one or more precious minerals in the Earth's crust. Ores of Aluminium: Bauxite – Al₂O₃ .2H₂O, Corundum – Al₂O₃ , Cryolite – Na₃AlF₆ . Ores of Iron - Siderite - Iron carbonate (FeCO₃), Hematite (ferric oxide, Fe₂O₃), Magnetite - Iron Oxide (Fe₃O₄). Monazite is an ore for thorium, lanthanum, and cerium. Metallurgy - Extraction of metals from their ores which naturally occur in nature.

The ore is heated in a regular supply of air in a furnace at a temperature below the melting point of the metal to convert them into metal oxides. It is easier to obtain a metal from its oxide, as compared to its sulphides and carbonates. Hence, prior to reduction, the metal sulphides and carbonates must be converted into metal oxides.
Calcination: The carbonate ores are changed into oxides by heating strongly in limited air. Both Roasting and Calcination are processes used in refinement of ores and extraction of metals.

Coke (Smokeless fuel) - It is most commonly used as a fuel for fires, furnaces, and blacksmithing.It is used in blast furnaces to produce iron from its ore. It is used in production of water gas {CO (Carbon monoxide) + H₂ (Hydrogen)} and producer gas (CO + N₂). Reducing agent - Reduces others while itself gets oxidized by losing electrons.

In the electrolytic refining process, the impure metal is made the anode and a thin strip of pure metal is made the cathode. On passing current, zinc from the electrolyte is deposited at the cathode while an equivalent amount of zinc from the anode goes into the electrolyte. Therefore, pure zinc is obtained on the cathode. Reaction at the Cathode: Zn²⁺ (aq) + 2e⁻ → Zn(s).

ignition with Ferric oxide is called the thermite reaction. This is an exothermic process that releases heat along with its end products. Iron produced in this cycle is in a liquid/molten state.
The reaction is - Fe₂O₃ (Ferric oxide) + Al (Aluminum ) →Al₂O₃ (Aluminum oxide) + 2 Fe(iron). Thermite reaction is utilized for the welding of rails (joining metals) called thermite welding.

Rusting - It is the phenomenon of a reddish-brown coating forming on the surface of iron due to the action of wet air. Galvanization - It is the process of applying a protective zinc coating to steel or iron, to prevent rusting.

A naturally occurring solid material from which a metal or valuable mineral can be extracted profitably. Important Metals and their Ores : Aluminum - Bauxite, Antimony - Stibnite, Calcium and Magnesium - Dolomite, Lead - Galena, Tin - Cassiterite, Gold - Calaverite.

Bronze is a metal alloy that primarily contains copper and approx 12% tin. Other elements—such as aluminum, arsenic, manganese, phosphorus, and silicon—are also added to yield different properties. Tin is added to copper to enhance its strength, hardness, and corrosion resistance.

Malleability is the physical property of metals by which they can be shaped into thin sheets without cracking.

Froth flotation is a process that uses a mixture of water and pine oil to create bubbles in a tank, allowing for the separation of sulfide ores based on differences in their wetting properties compared to gangue particles.