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What is Lead? Origin / Meaning of the name Lead
The English name 'lead' is derived from the Celtic word 'luaide'
meaning reddish, because of the colour of red lead, or lead
tetroxide. Red lead was prepared by heating white lead to a very
high temperature. It was used as a pigment in the production of
used in painting and in particular for illuminating manuscripts.
Origin / Meaning
of the symbol for Lead (Pb)
The symbol for lead 'Pb' originates from the word 'plumbum' which
is the Latin name for lead. A Roman worker in lead was called a
plumbarius, hence the name plumber which started to be used in
the 19th century when lead water pipes became the principal work
of the trade. Plumbism is the
medical term for lead poisoning.
What is Lead? Periodic Table Group and Classification of the Lead Element
Elements can be classified based on their physical states (States
of Matter) e.g. gas, solid or liquid. This element is a solid. Lead
is classified
in the 'Other Metals' section which can be located in groups 13,
14, and 15 of the Periodic Table. All of these elements are solid,
have a relatively high density and are opaque. In a general
overview of the element we can at first describe Lead as a
solid. It is a bluish-white metallic element which is seldom
found uncombined in nature, however, a compound of lead, called
galena, is widely distributed. The chief producers of lead are
the USA, Australia and Canada. Nearly 75%
of all the elements in the Periodic Table are classified as
metals which are detailed in the
List of Metals.
What is Lead? The
Properties of the Lead Element
Properties. Lead is a heavy
metal which has a brilliant silvery luster on a
freshly cut surface, but which soon tarnishes to a dull blue-gray
color. It is soft, easily fused (melting at 327°), and quite
malleable, but has little toughness or strength.
For additional facts and
information refer to Lead
Properties.
Facts about the
Discovery and
History of the Lead
Element
Lead was discovered was
discovered in Ancient times and used by the ancient Egyptians,
Greeks, Romans and Chinese. Galena, lead sulfide, the ore it could
easily be extracted from in open fires and was used widely for
cosmetics by the Ancient Egyptians. Heavy and resistant to
water, lead was used by the ancients making of weights and
sinkers. The ancient Romans used lead for making water pipes,
cooking utensils and storage vessels which were used in most
major cities in the empire. Lead is one of the metals referred to
as one of the 'Metals of Antiquity'. The ancient 'Metals of
Antiquity' together with their approximate dates of discovery
and use are Gold (6000BC),
Copper (9000BC),
Silver (4000BC), Lead (6400BC),
Tin (3000BC),
Iron (1500BC) and
Mercury (1500BC).
What is Lead? Occurrence of the Lead Element
Lead is found in nature chiefly as the sulphide (PbS), called
galena; to a much smaller extent it occurs as carbonate,
sulphate, chromate, and in a few other forms.
Extracted chiefly from galena
Found in ore with
Zinc,
Silver and (most abundantly)
Copper
Abundances of the element in different environments
% in Universe
1×10-6%
% in Sun 1×10-6%
% in Meteorites 0.00014%
% in Earth's Crust 0.00099%
% in Oceans 3×10-9%
% in Humans 0.00017%
Changes in the Uses of Lead
- Damage to the environment
Due to the toxic nature of lead many products containing the
element are no longer being manufactured because of the risk of
lead poisoning and damage to the environment.
Leaded gasoline (tetraethyl
lead) was once believed to have great advantages in improving
the performance of car engines. However, when it gets hot,
tetraethyl lead breaks down in a car engine and elemental lead
is formed which polluted the atmosphere. Lead paint and lead
water and sewer pipes for plumbing are no longer being
manufactured.
Uses of Lead
Lead continues to be used in the following:
Lead-acid batteries
Weights
Solders
Pewters
Fusible alloys
Radiation shields -
Shielding against radiation. In its metallic form, lead is used
as a protective shielding against radiographs. In dentistry,
lead acts as a protective shield against the radiographic beam
and is found in the lead apron and walls of the surrounding room.
Lead Oxides
and Compounds
Lead oxides: Lead forms a number of oxides, the most important
of which are litharge, red lead (minium), and lead peroxide.
Compounds: lead acetate is used in insecticides and dyeing of
cloth, lead fluoride is used to make lasers and
lead stearate is used to make soaps, waxes and paint |