Lead is a bluish-white lustrous metal. It is very soft,
highly malleable, ductile, and a relatively poor conductor of electricity. It
is very resistant to corrosion but tarnishes upon exposure to air. Lead pipes
bearing the insignia of Roman emperors, used as drains from the baths, are
still in service. Alloys include pewter and solder. Tetraethyl
lead (PbEt4) is still used in some grades of petrol (gasoline) but is being
phased out on environmental grounds.
Lead isotopes are the end products of each of the three series of naturally occurring radioactive elements.
Name: Lead
Symbol: Pb
Atomic number: 82
Atomic weight: 207.2 (1) [see notes g m]
Standard state: solid at 298 K
CAS Registry ID: 7439-92-1
Group in periodic table: 14
Group name: (none)
Period in periodic table: 6
Block in periodic table: p-block
Colour: bluish white
Classification: Metallic
historical information
Lead has been known since ancient times Origin of name is from the Anglo-Saxon word "lead" the origin of the element symbol "Pb" is from the Latin, plumbum" which means "liquid silver" (very cool!).
Lead has been known for ages and is actually mentioned in Exodus (see if you can find it). Alchemists believed lead to be the oldest metal and associated it with the planet Saturn. They spent a lot of time trying to "transmute" lead into gold.
Lead is one of the elements which has an alchemical symbol, though it is hard to describe....but it kind of looks like the number '5'
Sometime prior to the autumn of 1803, the Englishman John Dalton was able to explain the results of some of his studies by assuming that matter is composed of atoms and that all samples of any given compound consist of the same combination of these atoms. Dalton also noted that in series of compounds, the ratios of the masses of the second element that combine with a given weight of the first element can be reduced to small whole numbers (the law of multiple proportions). This was further evidence for atoms. Dalton's theory of atoms was published by Thomas Thomson in the 3rd edition of his System of Chemistry in 1807 and in a paper about strontium oxalates published in the Philosophical Transactions. Dalton published these ideas himself in the following year in the New System of Chemical Philosophy. The symbol used by Dalton for lead is a circle with an upper case L in the center
Physical properties
Melting point: 600.61 [or 327.46 °C (621.43 °F)] K
Boiling point: 2022 [or 1749 °C (3180 °F)] K
Density of solid: 11340 kg m-3 (most dense in the whole table...thus far)
Orbital properties
Ground state electron configuration: [Xe].4f14.5d10.6s2.6p2
Shell structure: 2.8.18.32.18.4
Term symbol: 3P0
Isolation
There is usually little need to make lead metal in the laboratory as it is so cheap and readily available. Lead is isolated from the sulphide, PbS. The process involves burning in a restricted air flow followed by reduction of the resulting oxide PbO with carbon.
PbS + 3/2O2 → PbO + SO2
PbO + C → Pb + CO
PbO + CO → Pb + CO2
This gives lead usually contaminated with metals such as antimony, arsenic, copper, gold, silver, tin, and zinc. A fairly complex process is used to strip out these impurities.
Lead isotopes are the end products of each of the three series of naturally occurring radioactive elements.
Name: Lead
Symbol: Pb
Atomic number: 82
Atomic weight: 207.2 (1) [see notes g m]
Standard state: solid at 298 K
CAS Registry ID: 7439-92-1
Group in periodic table: 14
Group name: (none)
Period in periodic table: 6
Block in periodic table: p-block
Colour: bluish white
Classification: Metallic
historical information
Lead has been known since ancient times Origin of name is from the Anglo-Saxon word "lead" the origin of the element symbol "Pb" is from the Latin, plumbum" which means "liquid silver" (very cool!).
Lead has been known for ages and is actually mentioned in Exodus (see if you can find it). Alchemists believed lead to be the oldest metal and associated it with the planet Saturn. They spent a lot of time trying to "transmute" lead into gold.
Lead is one of the elements which has an alchemical symbol, though it is hard to describe....but it kind of looks like the number '5'
Sometime prior to the autumn of 1803, the Englishman John Dalton was able to explain the results of some of his studies by assuming that matter is composed of atoms and that all samples of any given compound consist of the same combination of these atoms. Dalton also noted that in series of compounds, the ratios of the masses of the second element that combine with a given weight of the first element can be reduced to small whole numbers (the law of multiple proportions). This was further evidence for atoms. Dalton's theory of atoms was published by Thomas Thomson in the 3rd edition of his System of Chemistry in 1807 and in a paper about strontium oxalates published in the Philosophical Transactions. Dalton published these ideas himself in the following year in the New System of Chemical Philosophy. The symbol used by Dalton for lead is a circle with an upper case L in the center
Physical properties
Melting point: 600.61 [or 327.46 °C (621.43 °F)] K
Boiling point: 2022 [or 1749 °C (3180 °F)] K
Density of solid: 11340 kg m-3 (most dense in the whole table...thus far)
Orbital properties
Ground state electron configuration: [Xe].4f14.5d10.6s2.6p2
Shell structure: 2.8.18.32.18.4
Term symbol: 3P0
Isolation
There is usually little need to make lead metal in the laboratory as it is so cheap and readily available. Lead is isolated from the sulphide, PbS. The process involves burning in a restricted air flow followed by reduction of the resulting oxide PbO with carbon.
PbS + 3/2O2 → PbO + SO2
PbO + C → Pb + CO
PbO + CO → Pb + CO2
This gives lead usually contaminated with metals such as antimony, arsenic, copper, gold, silver, tin, and zinc. A fairly complex process is used to strip out these impurities.
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