1.2 Metals and metal compounds

Metals and metal compounds are found in many different forms in the nature and man-made chemicals. It is important to distinguish between the pure element vs. the ionic form of a metal found in solid and/or solution state. Listed below are some commonly found forms of metals and their compounds. Brief description is also provided to characterize their differences.

A. Earth’s Crust – major ores-

native ores: Au, Ag, Pt, Cu

oxide ores: iron, aluminum, manganese, tin

sulfide ores: zinc, cadmium, mercury, copper, lead, nickel, cobalt, silver

carbonate ores: iron, lead, zinc, copper, calcium, barium, magnesium, strontium

halides: sodium, potassium, magnesium, calcium, silver

sulfates: calcium, strontium, barium, lead

silicates: beryllium, zinc, nickel

phosphates: calcium

B. Oceans

A ton of sea water contains about 55 lbs sodium chloride, 2.5 lbs of magnesium, 1.75 lbs of sulfur, 0.8 lbs calcium, 0.75 lbs potassium, 0.13 lbs bromine and smaller quantities of boron, fluorine and iodine and the metals, strontium, copper, iron, lead, zinc, uranium, silver, gold and even radon.

C. Human Blood

contains 85.2 mM of Na, 44.5 mM of K, 8.59 mM of iron, 2.42 mM of calcium, 1.57 mM of magnesium, 138.4 μM of zinc, 14.8 μM of copper, 2.18 μM of manganese and 0.71 μM of cobalt.

D. Municipal Water

Na+, Ca2+, Mg2+, Fe3+ and Mn2+ are found along with bicarbonate, chloride, sulfate and silicate anions mainly. On evaporation or boiling, calcium sulfate, carbonate and silicate form clogging scales with low thermal conductivity in boilers. Hard water contains excessive amount of Ca2+ and Mg2+ and these metal ions form insoluble salts with soap and detergent.

E. Pure Metals and Alloys – in consumer goods and elsewhere

bronze: 70-95% Cu, 1-25% Zn, 1-18% Sn

solder: 67% Pb, 33% Sn

battery plate: 94% Pb, 6% Sb

dentist amalgam: 50% Hg, 35% Ag, 13% Sn, 1.5% Cu, 0.5% Zn

sterling silver: 92.5% Ag, 7.5% Cu

18 carat yellow gold: 75% Au, 12.5% Ag, 12.5% Cu

18 carat white gold: 75% Au, 3.5% Cu, 16.5% Ni, 5% Zn

yellow brass: 67% Cu, 33% Zn

steels: manganese alloy steel: Fe + 10-18% Mn (railroad rails)

silicon alloy steel: Fe + 1-5% Si (magnets)

alnico: Fe + Al, Ni, Co (permanent magnets)

chrom-vanadium alloy steel: Fe + 1-10% Cr + 0.15% V (axles)

stainless steel: Fe + 14-18% Cr + 7-9% Ni (cutlery, instruments)

high-speed steels: Fe + 14-20% W or 6-12% Mo (high-speed cutting tools)

nickel alloy steel: Fe + 2-4% Ni (drive shafts, gears, cables)

mild carbon steels: Fe + up to ~0.2% C (sheet iron, wire & pipes)

medium carbon steels: Fe + 0.2-0.6% C (rails, structural steel, boiler plate)

high carbon steels: Fe + 0.6 to 1.5% C (surgical instr., razor blades, springs, cutlery)

monel metal: Ni + Cu + a little Fe – highly resistive to oxidation

nichrome and chromel: alloys containing Ni, Fe and Cr – are resistant to oxidation at high temps and show high electric resistance (elec. heating wires, stoves, toasters, irons)

bullets and bearings: Pb hardened with 10-20% Sb.

Bi/Sn/Pb alloys: low melting – used for elec. fuses, safety plugs, automatic safety plugs

Roses metal: 50% Bi, 25% Pb, 25% Sn – melts at 94 °C

Woods metal: 50% Bi, 25% Pb, 12.5% Sn, 12.5% Cd – melts at 65.5 °C

Ru/Pt alloys: dental alloys and jewelry

Ir/Pt alloys: very hard and permanent alloys used for pen tips, surgical tools, elec. equipment

Pd/Pt/Au alloys: dental alloys (orthodontic appliances) jewelry, lab ware

89.9% Pt + 10.1% Ir alloy: The international standard kilogram and standard meter are made of this alloy because of permanence and low coefficient of thermal expansion

magnalium: Al + 1-15% Mg + 0-1.75% Cu – construction (lighter, harder, stronger than Al)

tin plate: iron coated with Sn

chromium plate: iron coated with Cr

cadmium plate: iron coated with Cd (attractive and resists corrosion well)

galvanized iron: iron coated with zinc (resists corrosion well)

magnesium metal: corrosion prevention

titanium metal (and alloys): strong light and resists corrosion (aircraft manufact.)

tungsten metal: m.p. 3370 °C (highest of the metals) – filament in elec. lamps, sparkplug contacts.

copper metal: electrical wiring, pipes

cadmium metal rods: nuclear reactor use – absorbs neutrons and controls chain reaction

mercury metal: liquid used in barometers, vacuum pumps, elec. contacts, lamps

aluminum metal: construction (airplane), elec. wiring, cooking utensils

platinum metal: electrodes, equipment for handling corrosive liquids and gases, electrical contacts, thermocouples, jewelry, dental appliances

F. Metals and Their Compounds as Catalysts

iron – cat. in NH3 manuf.; Fe (or Pt or Cr) in diamond manufacture

Fe2O3 – cat. in water-gas shift reaction

cobalt – finely divided – cat. in hydrogenation of CO & CO2 with the formation of      hydrocarbons and for oxidation of ammonia

nickel – cat. in steam-hydrocarbon reforming process – (or Pd or Pt or Ag or CoO) – in H2 + O2 fuel cell

copper – cat. in Rochow process (mf. of silicones)

Al2O3 – cat. in manufacture of graphite

Pt – finely divided forms (Pt black or Pt sponge): cat. in oxidation of SO2 (contact process); cat. in oxidation of NH3 to NO

Ru3(CO)12 – cat. in water-gas shift reaction

RhCl(PPh3)3 – cat. in olefin hydrogenation

Co2(CO)8 – cat. in hydroformylation reactions (C=C → CH−CHO)

Et3Al + TiCl3 – cat. in polymerization of olefins (C=C → C−C−C)

Ni(acac)2 – cat. in cyclo-oligomerization of acetylene

G. Metal Compounds in Consumer Goods, Industrial Processes, Etc.

metal hydrides (e.g. CaH2) – chemical dehydrating and reducing agents

intercalation compounds of graphite – new anisotropic conductors

Na2CO3 – for CO2 absorption

CaCO3 in lime production

silicates: Ca2Mg5(Si4O11)2(OH)2 – tremolite (asbestos)

K(Mg,Fe)(OH)2(AlSi3O10) – mica

Mx/n[(AlO2)x(SiO2)y]•2H2O (M=Na+, K+ or Ca2+) – zeolites

Na2O•xSiO2 and CaO•xSiO2 – glass

Na2SiO3•xSiO2 – silicate cement

NaNO3, KNO3: fertilizers and used in explosives industry

M(N3)2: azides of Pb, Hg and Ba – explode on striking; used in detonation caps

CaH4(PO4)2 and other phosphate fertilizers

NaH2PO4 and other orthophosphates and pyrophosphates used in water conditioning, detergents, baking products, etc.

M5(P3O10) – tripolyphosphate – control hardness of water

Zn[(RO)2PS2]2: lubricating oil additives

NaOH, CaO, Ca(OH)2: mortar, plaster, cement; manufacture of soap

Na2O2: bleaching agent

NaO2 – CO2 removal; O2 generator

CaS2, CaS5 – fungicides

Na2Sx – polysulfides used in rubber manufacture

NaOH/Na2S/Na2CO3: Kraft pulp

CaHSO3/MgHSO3/SO2: sulfite pulp

Na2S2O4 – dithionates: pulp bleaching

Na2SO3, NaHSO3, CaSO3, Ca(HSO3)2, Ca(OC1)2, NaOCl, NaClO3: bleaching

AgBr: photographic film


Some Important applications of alkali metal and their compounds can be found here:


Common Ions – Names and Formulae

Anion Name
H Hydride
F Fluoride
Cl Chloride
Br Bromide
I Iodide
O 2- Oxide
S 2- Sulfide
N 3- Nitride
P 3- Phosphide
Compound Ions Present Name
NaCl Na +, Cl sodium chloride
KI K +, I potassium iodide
CaS Ca 2+, S 2- calcium sulfide
Li3N Li +, N 3- lithium nitride
CsBr Cs +, Br cesium bromide
MgO Mg 2+, O 2- magnesium oxide
Ion Name Ion Name
NH4 + Ammonium CO3 2- carbonate
NO Nitrite HCO3 hydrogen carbonate

(bicarbonate is a widely used common name)

NO3 Nitrate
SO3 2- Sulfite
SO4 2- Sulfate ClO hypochlorite
HSO4 hydrogen sulfate

(bisulfate is a widely use common name)

ClO2 chlorite
ClO3 chlorate
ClO4 perchlorate
OH Hydroxide C2H3O2 acetate
CN Cyanide MnO4 permanganate
PO4 3- Phosphate Cr2O7 2- dichromate
HPO42- hydrogen phosphate CrO4 2- chromate
H2PO4 dihydrogen phosphate O2 2- peroxide
Ion Systematic Name Alternate Name
Fe 3+ iron (III) Ferric
Fe 2+ iron (II) Ferrous
Cu 2+ copper (II) Cupric
Cu + copper (I) Cuprous
Co 3+ cobalt (III) Cobaltic
Co 2+ cobalt (II) cobaltous
Sn 4+ tin (IV) Stannic
Sn 2+ tin (II) Stannous
Pb 4+ lead (IV) Plumbic
Pb 2+ lead (II) plumbous
Hg2+ mercury (II) Mercuric
Hg22+* mercury (I) mercurous
Compound Systematic Name
N2O dinitrogen monoxide
NO nitrogen monoxide
NO2 nitrogen dioxide
N2O3 dinitrogen trioxide
N2O4 dinitrogen tetroxide
N2O5 dinitrogen pentoxide


Icon for the Creative Commons Attribution 4.0 International License

Inorganic Chemistry for Chemical Engineers by Vishakha Monga; Paul Flowers; Klaus Theopold; William R. Robinson; and Richard Langley is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

Share This Book