Metallurgy - Formula Sheet

Thermodynamic Principles

Gibbs Free Energy Change: \(\Delta G = \Delta H - T\Delta S\)

• \(\Delta G\): Change in standard free energy.
• \(\Delta H\): Change in enthalpy (heat content).
• \(T\): Absolute temperature in Kelvin.
• \(\Delta S\): Change in entropy (randomness).

For a reaction to be spontaneous, \(\Delta G\) must be negative.

Electrochemical Principles

Standard Free Energy and EMF: \(\Delta G^{0} = -nFE^{0}\)

• \(n\): Number of moles of electrons exchanged.
• \(F\): Faraday's constant (\(96485\) \(C\,mol^{-1}\)).
• \(E^{0}\): Standard electrode potential of the cell.

A positive \(E^{0}\) value results in a negative \(\Delta G^{0}\), indicating a spontaneous process.

Specific Metallurgical Formulas

• Bauxite (Aluminum Ore): \(Al_{2}O_{3}.nH_{2}O\)
• Haematite (Iron Ore): \(Fe_{2}O_{3}\)
• Magnetite (Iron Ore): \(Fe_{3}O_{4}\)
• Copper Pyrite: \(CuFeS_{2}\)
• Calamine (Zinc Ore): \(ZnCO_{3}\)