metals and metallurgy

Minerals are named by ___, not chemical, names

common

most metals are found in inorganic compounds in these

minerals

oxides, sulfides, carbonates

Most important metals are found in minerals as

Metallurgy

The science and technology of extracting metals from their natural sources and preparing them for practical use.

pyrometallurgy

the use of high temperature to alter or reduce minerals

Calcination

heating an ore to bring about its decomposition and elimination of a volatile product.

roasting

a thermal reaction between an ore and the furnace atmosphere (often oxygen)

smelting

melting process in which materials formed during reactions separate into two or more layers.

refining

the treatment of a crude, relatively impure metal to improve its purity and better define its composition.

Hematite (Fe2O3 ) and magnetite (Fe3O4 )

common iron oxides reduced

silicon, manganese, phosphorus, sulfur, carbon

crude molten iron impurities

Oxygen

steel impurity oxidizer

Calcium Oxide

phosphorus impurity oxidizer

Hydrometallurgy

techniques in which metal is extracted from ore via the use of aqueous reactions.

leaching

a process in which a metalcontaining compound is selectively dissolved.

water

leaching compound used to water-soluble metal containing minerals

acid, base, salt solutions

leaching compound used to non-water-soluble metal containing minerals

Bayer Process

This is a method of purifying bauxite (aluminum ore)

filtration

The soluble aluminate ion is separated from the insoluble impurities (SiO2 and Fe3O3 ) by

electrometallurgy

The reduction of metal ores or refining of metals by use of electricity is called

Downs Cell

sodium (NaCl) electrolysis site

Hall process

Al2O3 is dissolved in molten cryolite (Na2AlF6 ), and Al3+ is reduced to molten Al

cathode anode reaction

copper production through electrometallurgy

metal physical properties

• heat and electricity conductivity

• malleable

• ductile

• packed

Electron-Sea Model

Metals can be thought of as cations suspended in “sea” of valence electrons.

molecular orbital model

explains trends in melting point, boiling point, heat of fusion, etc.

molecular orbital model

The model suggests these properties should increase with increasing number of valence electrons

energy bands

explains trends through molecular orbitals formes as metal atoms bond with each other

apex of attractions

happens in the center of transition metals

alloys

mixtures of elements that have properties characteristic of metals.

uniformly

Components of alloys are dispersed

substitutional alloys

solute particles take the place of solvent metal atoms

interstitial alloys

solute particles find their way into the holes between solvent metal atoms.

substitutional alloys

The particles in these alloys are quite close in size.

interstitial alloys

In this type of alloy the solute particles are smaller than the solvent particles

Intermetallic compounds

homogeneous alloys with definite properties and compositions.

Co5Sm

used for permanent magnets in headsets and speakers.

transition metals

the elements in the d block of the periodic table.