Metallic Elements Compounds Lesson 26 by Owen Borville 11.12.2025
Most metals come from minerals, which are solid naturally occurring inorganic substances in the Earth's crust with defined chemical properties, composition, and internal crystal structure.
Ore minerals occur if there is enough deposited in a certain location to allow economic recovery of a particular metal-containing mineral. Metallic elements extend across group columns 1-15 in the central and left portion of the Periodic Table.
Metallic minerals include single element metallic minerals, carbonates, halides, oxides, phosphates, silicates, sulfides, and sulfates.
The most abundant metals, which exist as minerals in the Earth's crust, are aluminum, iron, calcium, magnesium, sodium, potassium, titanium, and manganese. Seawater is a rich source of some metal ions, including sodium Na+, magnesium Mg+, and calcium Ca2+.
Manganese nodules cover large regions of the ocean floor containing the element manganese, along with iron, nickel, copper, and cobalt in a chemical combination.
Metallurgy is the science and technology of separating metals from their ores and of compounding alloys. An alloy is a solid solution of two or more metals or of a metal or metals with one or more nonmetals. The steps in recovery of a metal from its ore include preparation of the ore, production of the metal, and purification of the metal.
Metals inside ore minerals are separated using several techniques. (1) Using the flotation method, the ore is finely ground into small particles, added to a water and chemical mixture, and beaten to form a froth which floats to the surface by way of air bubbles and which is skimmed off so that metals can be recovered. (2) magnets are used to attract ferromagnetic metals from the ore. (3) mercury amalgams use liquid mercury mixed with the ore to make an alloy to help separate the metal (gold, silver, zinc) from the ore then heated to vaporize the mercury and the pure metal is left behind.
Metals are reduced from their positive oxidation state to a free metal. The purity of the metal from reduction from its combined form depends on the reduction potential of the metal. Metals can be reduced by carbon or carbon monoxide for metals like iron and zinc. Electrolysis is used for highly reactive metals like aluminum through a molten salt. Metallothermic reduction is used with oxides, sulfides, chlorides, or fluorides. hydrogen reduction, and solid oxide electrolysis are other methods of reduction used for the separation of specific metals. Pyrometallurgy is a metallurgic process carried out at high temperature for reduction purposes.
Chemical reduction allows a more electropositive metal to be used as a reducing agent to separate a less electropositive metal from its compound at high temperature. For example, vanadium is reduced from its oxide V2O5 using a stronger reducing agent like calcium, aluminum, or magnesium using metallothermic reduction.
Electrolytic reduction is used for very electropositive metals like sodium, magnesium, and aluminum. A direct electric current is passed through a molten or dissolved salt of the metal, causing the metal ions at the cathode to gain electrons and deposit as a pure metal, while non-metal ions are oxidized at the anode.
Steel is an iron alloy that contains up to 1.4 percent carbon and other elements. The basic oxygen process is one method of steel production, where pure oxygen is blown through the mixture, oxidizing the impure components from the steel components. While plain steel is used in sheet products and tools, high strength steel is used in construction and steam turbines. Stainless steel is used in kitchen utensils and razor blades.
Metals separated by reduction often need more work to remove impurities, depending on how the final product will be used.
The Mond process is used for the purification of nickel: Ni(s) + 4CO(g) => Ni(CO)4(g)
Pure metallic nickel is recovered from Ni(CO)4(g) by heating the gas at 200 degrees C: Ni(CO)4(g) =>Ni(s) + 4CO(g)
Electrolysis (electrorefining), involves the purification of metals with an electrolytic cell is used where the anode involves oxidation of metallic electrons (giving away) while the cathode involves reduction of metallic electrons (gaining).
Zone refining (Ge, Si, Ga, In, B) allows metals to be purified in the electronics and semiconductor industries where a mobile heating element (coil) is moved along a metal rod, causing impurities to concentrate in the molten zone and leaving behind a highly purified solid.
Band theory of conductivity is a model used to study electric conductivity in a variety of metals where delocalized electrons move freely through bands formed by overlapping molecular orbitals (valence and conduction bands overlap), making them excellent conductors of electricity. In contrast, semiconductors have a small band gap that requires more energy for electrons to cross, while insulator have a large band gap that prevents electron movement and makes them poor conductors of electricity. In metals, the band gap is mostly nonexistent and metals feature a series of positive charges submerged in a sea of delocalized electrons.
Semiconductors are elements that are normally not conductors of electricity, but will conduct electricity at elevated temperatures or when combined with a small amount of certain other elements. Group 14 of the Periodic Table are most know for their semiconductor capability, including silicon and germanium. Semiconductors have a small energy band gap between the valence band and conduction band for electrons to cross. Insulators, however, are ineffective conductors of electricity because their band gap is large and electrons cannot move freely.
Doping is the process of adding small amounts of impurities to the element or material to enhance the ability of the semiconductor to conduct electricity. Solids containing or doped with donor impurities, which add free electrons, are called n-type semiconductors. Semiconductors that contain or are doped with acceptor impurities are called p-type semiconductors, which create excess holes or missing electrons which act as positive charge carriers.
Periodic Trends in Metallic Properties: Metals are generally: (1) lustrous or shiny in appearance (2) solid at room temperature (except mercury) (3) good conductors of heat and electricity (4) malleable (ability to be hammered flat) (5) ductile (can be drawn into wires) (6) classified as representative (Group A: 1-2, 13-18) or transition (Group B: 3-12) based on position on the Periodic Table.
Periodic Trends: Electronegativity (the atom's ability to attract shared electrons in a chemical bond) increases left to right across a period and up a column. Metallic character decreases left to right across a period and up a column. Metals form positive ions or cations. Metals have positive oxidation numbers.
Alkali Metals Common Properties: Common oxidation state (+1). Alkali metals do not occur free in nature, but are combined or bonded to halides, sulfates, carbonates, and silicates. Alkali metals are found dissolved in seawater due to geologic erosion of minerals. Sodium (Na) is obtained from electrolysis of molten salt. Potassium (K) is obtained from distillation of molten KCl in the presence of sodium vapor.
Alkali metals such as sodium and potassium react with water to form hydroxides and react with oxygen to from oxides, peroxides, and superoxides.
Alkali metals dissolve in liquid ammonia to form powerful reducing agents (Na+ and K+)
Alkali metals: compounds of sodium and potassium: Sodium carbonate (Na2CO3) is soda ash and important in industrial processes, including the manufacture of soaps, detergents, medicine, and food additives.
Soda ash is produced by the Solvay process:
NH3(aq) + NaCl(aq) + H2CO3(aq) => NaHCO3(s) + NH4Cl(aq)
2NaHCO3(s) => Na2CO3(s) + CO2(g) + H2O(g)
Alternate production of soda ash- heating the mineral trona: [Na5(CO3)2(HCO3)*2H2O]
2Na5(CO3)2(HCO3)+2H2O(s) =>5Na2CO3(s) + CO2(g) + 3H2O(g)
The heating of trona, also called calcification, involves the heating of the mineral to remove water and carbon dioxide, leaving behind sodium carbonate (soda ash).
Sodium and potassium hydroxides are prepared by the electrolysis of chloride salts. These are strong bases and highly soluble in water.
Sodium nitrate is found in Chile saltpeter and decomposes at about 500 degrees C: 2NaNO3(s) =>2NaNO2(s) + O2(g)
Potassium nitrate (salt peter) is prepared by: KCl(aq) + NaNO3(aq) =>KNO3(aq) + NaCl(aq)
Alkaline Earth Metals: Common Properties (except Be) Less electropositive than alkali metals. Less reactive than the alkali metals. Positive 2+ ions attain the stable electron configuration of the preceding noble gas. Oxidation number is commonly +2. All isotopes of radium are radioactive.
Alkaline Earth Metals: Magnesium is the sixth most common element in the Earth's crust (2.5%). Main magnesium ores are brucite [Mg(OH)2), dolomite (CaCO3*MgCO3) and epsomite (MgSO4*7H2O). Seawater is a source of magnesium (1.3 grams of magnesium in each kg of seawater). Metallic magnesium is obtained by electrolysis from its molten chloride MgCl2.
Magnesium makes a strongly basic hydroxide.
Magnesium reactions:
Mg(s) + H2O(g) => MgO(s) + H2(g)
2Mg(s) + O2(g) =>2MgO(s)
3Mg(s) + N2(g) =>Mg3N2(s)
Magnesium is essential to plant and animal life.
Alkaline Earth Metals: Calcium is (3.4%) of Earth's crust and occurs in limestone, calcite, chalk, and marble as CaCO3. In dolomite as CaCO3*MgCO3, In gypsum as CaSO4*2H2O, In fluorite as CaF2. Metallic calcium is best prepared by the electrolysis of molten calcium chloride (CaCl2).
Calcium reactions:
Ca(s) + 2H2O(l) => Ca(OH)2(aq) + H2(g)
CaCO3(s) =>CaO(s) + CO2(g)
CaO(s) + H2O(l) =>Ca(OH)2(aq)
Metallic calcium serves mainly as an alloying agent and is essential for living systems.
Aluminum is the most abundant metal and third most abundant element in the Earth's crust (7.5%). Elemental aluminum does not occur in nature. Principal aluminum ore is bauxite (Al2O3*2H2O). Other minerals containing aluminum: orthoclase (KAlSi3O8), beryl (Be3Al2Si6O18), cryolite (Na3AlF6), and corundum (Al2O3). Aluminum once was a precious metal until Hall developed a method of aluminum production.
Electrolytic production of aluminum is based on the Hall-Héroult process: electrolysis to extract aluminum from Al2O3 by dissolving Al2O3 in molten cryolite Na3AlF6 within a carbon-lined pot and passing an electric current through the mixture, which causes oxygen to be separated and react with the carbon anodes while molten aluminum collects at the bottom of the pot.
Aluminum reactions: Aluminum is amphoteric because it reacts with both acids and bases:
Acid reaction: 2Al(s) + 6HCl(aq) => 2AlCl3(aq) + 3H2(g)
Base reaction: 2Al(s) + 2NaOH(aq) + 2H2O(l)=>2NaAlO2(aq) + 3H2(g)
Oxide formation: 4Al(s) + 3O2(g) => 2Al2O3(s)
With metal oxides: 2Al(s) + Fe2O3(s) => Al2O3(l) + 2Fe(l)
Thermite reaction: 2Al(s) + Fe2O3(s) =>Al2O3(l) + 2Fe(l) (for the welding of steel and iron)
Aluminum chloride exists as a dimer, a molecule that forms when two identical or similar molecules (monomers) join together (AlCl3 exists as Al2Cl6) as a covalent bond dimer to achieve a stable octet.
Aluminum hydrates are well-defined series of compounds. Aluminum hydride (AlH3) is a polymer in which each aluminum atom is surrounded octahedrally by bridging hydrogen atoms.
Hydrolysis reaction: AlCl3(s) + 3H2O(l) =>Al(OH)3(s)+3HCl(aq)
Amphoterism: Al(OH)3(s) + 3H+(aq) =>Al3+(aq) + 3H2O(l)
Al(OH)3(s) + OH-(aq) =>Al(OH)4-(aq)
Formation of Alums (double sulfates): are formed through a chemical process involving the crystallization of a salt with two different metal sulfates, using the following formula:
M+M3+(SO4)2*12H2O
M+(metal ions possible ): K+, Na+, NH4+
M3+(metal ions possible): Al3-, Cr3+, Fe3+
Most metals come from minerals, which are solid naturally occurring inorganic substances in the Earth's crust with defined chemical properties, composition, and internal crystal structure.
Ore minerals occur if there is enough deposited in a certain location to allow economic recovery of a particular metal-containing mineral. Metallic elements extend across group columns 1-15 in the central and left portion of the Periodic Table.
Metallic minerals include single element metallic minerals, carbonates, halides, oxides, phosphates, silicates, sulfides, and sulfates.
The most abundant metals, which exist as minerals in the Earth's crust, are aluminum, iron, calcium, magnesium, sodium, potassium, titanium, and manganese. Seawater is a rich source of some metal ions, including sodium Na+, magnesium Mg+, and calcium Ca2+.
Manganese nodules cover large regions of the ocean floor containing the element manganese, along with iron, nickel, copper, and cobalt in a chemical combination.
Metallurgy is the science and technology of separating metals from their ores and of compounding alloys. An alloy is a solid solution of two or more metals or of a metal or metals with one or more nonmetals. The steps in recovery of a metal from its ore include preparation of the ore, production of the metal, and purification of the metal.
Metals inside ore minerals are separated using several techniques. (1) Using the flotation method, the ore is finely ground into small particles, added to a water and chemical mixture, and beaten to form a froth which floats to the surface by way of air bubbles and which is skimmed off so that metals can be recovered. (2) magnets are used to attract ferromagnetic metals from the ore. (3) mercury amalgams use liquid mercury mixed with the ore to make an alloy to help separate the metal (gold, silver, zinc) from the ore then heated to vaporize the mercury and the pure metal is left behind.
Metals are reduced from their positive oxidation state to a free metal. The purity of the metal from reduction from its combined form depends on the reduction potential of the metal. Metals can be reduced by carbon or carbon monoxide for metals like iron and zinc. Electrolysis is used for highly reactive metals like aluminum through a molten salt. Metallothermic reduction is used with oxides, sulfides, chlorides, or fluorides. hydrogen reduction, and solid oxide electrolysis are other methods of reduction used for the separation of specific metals. Pyrometallurgy is a metallurgic process carried out at high temperature for reduction purposes.
Chemical reduction allows a more electropositive metal to be used as a reducing agent to separate a less electropositive metal from its compound at high temperature. For example, vanadium is reduced from its oxide V2O5 using a stronger reducing agent like calcium, aluminum, or magnesium using metallothermic reduction.
Electrolytic reduction is used for very electropositive metals like sodium, magnesium, and aluminum. A direct electric current is passed through a molten or dissolved salt of the metal, causing the metal ions at the cathode to gain electrons and deposit as a pure metal, while non-metal ions are oxidized at the anode.
Steel is an iron alloy that contains up to 1.4 percent carbon and other elements. The basic oxygen process is one method of steel production, where pure oxygen is blown through the mixture, oxidizing the impure components from the steel components. While plain steel is used in sheet products and tools, high strength steel is used in construction and steam turbines. Stainless steel is used in kitchen utensils and razor blades.
Metals separated by reduction often need more work to remove impurities, depending on how the final product will be used.
The Mond process is used for the purification of nickel: Ni(s) + 4CO(g) => Ni(CO)4(g)
Pure metallic nickel is recovered from Ni(CO)4(g) by heating the gas at 200 degrees C: Ni(CO)4(g) =>Ni(s) + 4CO(g)
Electrolysis (electrorefining), involves the purification of metals with an electrolytic cell is used where the anode involves oxidation of metallic electrons (giving away) while the cathode involves reduction of metallic electrons (gaining).
Zone refining (Ge, Si, Ga, In, B) allows metals to be purified in the electronics and semiconductor industries where a mobile heating element (coil) is moved along a metal rod, causing impurities to concentrate in the molten zone and leaving behind a highly purified solid.
Band theory of conductivity is a model used to study electric conductivity in a variety of metals where delocalized electrons move freely through bands formed by overlapping molecular orbitals (valence and conduction bands overlap), making them excellent conductors of electricity. In contrast, semiconductors have a small band gap that requires more energy for electrons to cross, while insulator have a large band gap that prevents electron movement and makes them poor conductors of electricity. In metals, the band gap is mostly nonexistent and metals feature a series of positive charges submerged in a sea of delocalized electrons.
Semiconductors are elements that are normally not conductors of electricity, but will conduct electricity at elevated temperatures or when combined with a small amount of certain other elements. Group 14 of the Periodic Table are most know for their semiconductor capability, including silicon and germanium. Semiconductors have a small energy band gap between the valence band and conduction band for electrons to cross. Insulators, however, are ineffective conductors of electricity because their band gap is large and electrons cannot move freely.
Doping is the process of adding small amounts of impurities to the element or material to enhance the ability of the semiconductor to conduct electricity. Solids containing or doped with donor impurities, which add free electrons, are called n-type semiconductors. Semiconductors that contain or are doped with acceptor impurities are called p-type semiconductors, which create excess holes or missing electrons which act as positive charge carriers.
Periodic Trends in Metallic Properties: Metals are generally: (1) lustrous or shiny in appearance (2) solid at room temperature (except mercury) (3) good conductors of heat and electricity (4) malleable (ability to be hammered flat) (5) ductile (can be drawn into wires) (6) classified as representative (Group A: 1-2, 13-18) or transition (Group B: 3-12) based on position on the Periodic Table.
Periodic Trends: Electronegativity (the atom's ability to attract shared electrons in a chemical bond) increases left to right across a period and up a column. Metallic character decreases left to right across a period and up a column. Metals form positive ions or cations. Metals have positive oxidation numbers.
Alkali Metals Common Properties: Common oxidation state (+1). Alkali metals do not occur free in nature, but are combined or bonded to halides, sulfates, carbonates, and silicates. Alkali metals are found dissolved in seawater due to geologic erosion of minerals. Sodium (Na) is obtained from electrolysis of molten salt. Potassium (K) is obtained from distillation of molten KCl in the presence of sodium vapor.
Alkali metals such as sodium and potassium react with water to form hydroxides and react with oxygen to from oxides, peroxides, and superoxides.
Alkali metals dissolve in liquid ammonia to form powerful reducing agents (Na+ and K+)
Alkali metals: compounds of sodium and potassium: Sodium carbonate (Na2CO3) is soda ash and important in industrial processes, including the manufacture of soaps, detergents, medicine, and food additives.
Soda ash is produced by the Solvay process:
NH3(aq) + NaCl(aq) + H2CO3(aq) => NaHCO3(s) + NH4Cl(aq)
2NaHCO3(s) => Na2CO3(s) + CO2(g) + H2O(g)
Alternate production of soda ash- heating the mineral trona: [Na5(CO3)2(HCO3)*2H2O]
2Na5(CO3)2(HCO3)+2H2O(s) =>5Na2CO3(s) + CO2(g) + 3H2O(g)
The heating of trona, also called calcification, involves the heating of the mineral to remove water and carbon dioxide, leaving behind sodium carbonate (soda ash).
Sodium and potassium hydroxides are prepared by the electrolysis of chloride salts. These are strong bases and highly soluble in water.
Sodium nitrate is found in Chile saltpeter and decomposes at about 500 degrees C: 2NaNO3(s) =>2NaNO2(s) + O2(g)
Potassium nitrate (salt peter) is prepared by: KCl(aq) + NaNO3(aq) =>KNO3(aq) + NaCl(aq)
Alkaline Earth Metals: Common Properties (except Be) Less electropositive than alkali metals. Less reactive than the alkali metals. Positive 2+ ions attain the stable electron configuration of the preceding noble gas. Oxidation number is commonly +2. All isotopes of radium are radioactive.
Alkaline Earth Metals: Magnesium is the sixth most common element in the Earth's crust (2.5%). Main magnesium ores are brucite [Mg(OH)2), dolomite (CaCO3*MgCO3) and epsomite (MgSO4*7H2O). Seawater is a source of magnesium (1.3 grams of magnesium in each kg of seawater). Metallic magnesium is obtained by electrolysis from its molten chloride MgCl2.
Magnesium makes a strongly basic hydroxide.
Magnesium reactions:
Mg(s) + H2O(g) => MgO(s) + H2(g)
2Mg(s) + O2(g) =>2MgO(s)
3Mg(s) + N2(g) =>Mg3N2(s)
Magnesium is essential to plant and animal life.
Alkaline Earth Metals: Calcium is (3.4%) of Earth's crust and occurs in limestone, calcite, chalk, and marble as CaCO3. In dolomite as CaCO3*MgCO3, In gypsum as CaSO4*2H2O, In fluorite as CaF2. Metallic calcium is best prepared by the electrolysis of molten calcium chloride (CaCl2).
Calcium reactions:
Ca(s) + 2H2O(l) => Ca(OH)2(aq) + H2(g)
CaCO3(s) =>CaO(s) + CO2(g)
CaO(s) + H2O(l) =>Ca(OH)2(aq)
Metallic calcium serves mainly as an alloying agent and is essential for living systems.
Aluminum is the most abundant metal and third most abundant element in the Earth's crust (7.5%). Elemental aluminum does not occur in nature. Principal aluminum ore is bauxite (Al2O3*2H2O). Other minerals containing aluminum: orthoclase (KAlSi3O8), beryl (Be3Al2Si6O18), cryolite (Na3AlF6), and corundum (Al2O3). Aluminum once was a precious metal until Hall developed a method of aluminum production.
Electrolytic production of aluminum is based on the Hall-Héroult process: electrolysis to extract aluminum from Al2O3 by dissolving Al2O3 in molten cryolite Na3AlF6 within a carbon-lined pot and passing an electric current through the mixture, which causes oxygen to be separated and react with the carbon anodes while molten aluminum collects at the bottom of the pot.
Aluminum reactions: Aluminum is amphoteric because it reacts with both acids and bases:
Acid reaction: 2Al(s) + 6HCl(aq) => 2AlCl3(aq) + 3H2(g)
Base reaction: 2Al(s) + 2NaOH(aq) + 2H2O(l)=>2NaAlO2(aq) + 3H2(g)
Oxide formation: 4Al(s) + 3O2(g) => 2Al2O3(s)
With metal oxides: 2Al(s) + Fe2O3(s) => Al2O3(l) + 2Fe(l)
Thermite reaction: 2Al(s) + Fe2O3(s) =>Al2O3(l) + 2Fe(l) (for the welding of steel and iron)
Aluminum chloride exists as a dimer, a molecule that forms when two identical or similar molecules (monomers) join together (AlCl3 exists as Al2Cl6) as a covalent bond dimer to achieve a stable octet.
Aluminum hydrates are well-defined series of compounds. Aluminum hydride (AlH3) is a polymer in which each aluminum atom is surrounded octahedrally by bridging hydrogen atoms.
Hydrolysis reaction: AlCl3(s) + 3H2O(l) =>Al(OH)3(s)+3HCl(aq)
Amphoterism: Al(OH)3(s) + 3H+(aq) =>Al3+(aq) + 3H2O(l)
Al(OH)3(s) + OH-(aq) =>Al(OH)4-(aq)
Formation of Alums (double sulfates): are formed through a chemical process involving the crystallization of a salt with two different metal sulfates, using the following formula:
M+M3+(SO4)2*12H2O
M+(metal ions possible ): K+, Na+, NH4+
M3+(metal ions possible): Al3-, Cr3+, Fe3+