Element Lead, Pb, Poor Metal
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Lead History
The origin of the modern Russian name "svinets" is not clear. In the past it was not always clearly distinguished from tin. In most of Slavic languages such as Bulgarian, Serbo-Croatian, Czech, and in Polish lead is called as tin, olovo. The word similar to Russian svinets is found in Baltic languages: the Lithuanian svinas and the Latvian swins. The English lead was borrowed from the Irish luaide of unknown origin which, according to many sources, derived from Celtic loud or Sanskrite loka, which means reddish, because of the red colour of lead oxide (red lead). Greeks called it molybdos; the same name is used also in Modern Greek language. The Latin molibdaena derived from the Greek word was assigned both to lead glance PbS as well as much more rare molybdenite MoS2 and all other substances which leave black marks on bright-coloured surface, similarly to graphite and lead itself. Lead could be used for writing; that is why the German for pencil is "ein Bleistift" which means lead.
Lead Occurrence
Poor metal Lead abundance is 1.6x10-3 mass % in the Earth's crust, 0.03 µg /l (41.1 million tons), and 0.2 - 8.7 µg/l in river water. Around 80 lead containing minerals, the main of which is galena PbS, formed in the Earth crust are associated mostly with hydrothermal deposits. Numerous (around 90) secondary minerals such as are formed in complex ores oxidizing zones plenty of minerals are formed such as sulphates (anglesite PbSO4), carbonates (cerussite PbCO3), phosphates (pyromorphite Pb5(PO4)3Cl). Lead is diffused in biosphere, with small content in living matter (5x10-5%) and in sea water (3x10-9%). It is partially accumulated by clays from natural waters and then is sedimented by hydrogen sulphide, so it is accumulated in the hydrogen sulphide contaminated sea ooze as well as in dilsh and slates formed in it.
In atmosphere its content reaches 2x10-9-5x10-4 µg/m3. In adult human body it contens is about 7-15 mg.
Lead Neighbours
Chemical Elements |