Talk:Lead

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Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 12:19, 10 July 2005 by Femto (previous revision was that of 14:08, 9 July 2005).

Contents

[edit] Information Sources

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Lead. Additional text was taken directly from USGS Lead Statistics and Information, USGS Periodic Table - Lead, from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the main page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.

there are many reason to why metals have changed over the years.what do u think happend to pencil lead and why?

Pencils never used lead. It was actually graphite from the time it was first invented. It was just called "lead" due to its similarity. 68.32.134.183 01:02, 8 Jun 2005 (UTC)

"This true metal is highly resistant to corrosion" Are you sure that this is true? Lead has a rather negative reduction potential and is easily attacked by Oxygen... Its resistance to Sulfuric Acid is only due to the insolubility of PbSO4! --malbi

"Lead is the fourth most widely used metal after aluminium, copper and zinc." Isn't iron more widely used than lead? The article on iron says that it's the most common metal in the universe, and the article on aluminum says "Whether measured in terms of quantity or value, aluminium's use exceeds that of any other metal except iron", which would put iron at the top, then. -- Arteitle 07:42, 2 Aug 2003 (UTC)

That also depends on what you mean with "metal" - if you include salts, Calcium or even Sodium might have good chances as well...

By all means, if you think something is wrong then fix it -- All I know was from the sources I cite above (which may be wrong) and I also incorporated a good deal of text that was here before the conversion. --mav 23:55, 3 Aug 2003 (UTC)

[edit] Re isotope 204 stablility -- inconsistent?

The isotope table in the article notes that isotope 204 has a half-life of ">1.4E17 years". This seems to indicate that the isotope is not stable, according to my understanding of the term; yet the textual section on "Isotopes" indicates that lead has 4 stable isotopes, including 204. This seems inconsistent.

For comparison, I note that a determination that bismuth isotope 209 was determined to be "not stable after all" at a half life of 1.9E19 years.

I have also seen differing reports as to the stability of lead-204 against either alpha or beta decay. Some tables report it as a stable isotope while others give a very long half-life of ~10E17 years. This data point could actually be more than of just theoretical interest only, because the ratio of radiogenic lead to nonradiogenic lead (Lead-204 is not produced by any of the decay chains of the heavy long-lived radioactive isotopes) is one way to determine the age of a sample containing uranium, and such methods are often disputed by creationists who claim radioactive dating is wrong. --24.80.110.173 06:47, 7 August 2005 (UTC)

The article doesn't seem to mention the price of lead. This is an important thing to include. Tannin 10:39, 14 May 2005 (UTC)

[edit] Precautions

Doesn't seem to list any actual precautions that should be taken. -- eyrian

Simple, don't eat it. Lead is not nearly as toxic as the vast majority of other chemicals. Even if you did eat it, you'd be in more danger of intestinal rupture from lead chunks than lead poisoning.
Lead salts pose more of a danger, but even still, for most lead salts you'd need to consume large amounts for an extended period of time to have any ill effects.
Darrien 18:17, 2005 Jun 14 (UTC)
Good and well, but what about living on lead contaminated soil? I guess lead chunks aren't immediately dangerous, it's more a long-term environmental exposure type of problem, yes? Josh Parris ✉ 00:22, 15 Jun 2005 (UTC)
It depends on what kind of lead contaminated the soil. Any form of lead will leach into groundwater given enough time, but it would have to be a very toxic form of lead like an organometallic compound to pose any danger to someone just taking a stroll through the area.
Darrien 03:25, 2005 Jun 15 (UTC)
There have been a number of widely reported Playschool soil contaiminated with lead and shutdown type stories where I live; are kids playing in contaminated soil at any real risk? Josh Parris ✉ 03:48, 15 Jun 2005 (UTC)
I really can't answer a question like that without more information. Children *are* more susceptible to lead poisoning, but the media does have a history of sensationalizing stories such as these. Without hard facts, I can only say "it depends". If you have a genuine concern, I would recommend that you speak to a physician or toxicologist.
Darrien 03:14, 2005 Jun 16 (UTC)

Obviously no-one above has had the experience of finding out that your child has a high blood lead level. I have! Lead toxicity is a serious problem for children under 5 as it lowers IQ. The dangers should not be underplayed. Michael Glass 15:54, 27 April 2006 (UTC)

[edit] Fuel additive

Can somebody who knows more about it than me add some information on lead as a fuel additive? This is an odd omission. --WibblyLeMoende

Whilst I know nothing about it, I have added it. Josh Parris ✉ 07:20, 15 July 2005 (UTC)
Tetraethyl lead, perhaps? --24.80.110.173 06:47, 7 August 2005 (UTC)

[edit] Pencil Lead

According to the 'pencil lead' article, lead was never used in pencils, but graphite was instead mistaken for lead when it was discovered under a tree. I've read a book about inventions that would corroborate that story, and I somehow doubt lead would make enough of a streak to ever b e used to write with..

The pencil#history section says:

The prototypical pencil may have been the ancient Roman stylus, which was a thin metal stick used for scratching on papyrus, often made of lead. The word pencil comes from the Latin word penicillus which means "little tail".

But, for about 450 years pencils have had "lead cores" of graphite substances. Josh Parris 00:05, 16 November 2005 (UTC)
One book I read stated that molybdenite and graphite were used, but that molybdenite was mistaken for a lead mineral. It said that no lead was ever used. Lead solder (in contrast to lead-free solder) makes a streak, but it's much fainter than graphite.

[edit] lead,periodic element

[edit] Lead/ peroidic element

[edit] Plumber

The word plumber comes from lead in Latin (plumbum). In Spanish, lead is plomo, and a plomero is a plumber. All this *leads* me to believe that pipes in old cities are made of lead!!! Are we drinking lead in New York and other cities with old buildings and utilities? Remember, it is said that one of the causes of the Fall of the Roman Empire was a general lead poisoning of its population, which was worst in the ruling class. Is it true that we are eating lead whenever we eat tuna fish or sardines? (maybe in all canned food?) Maybe there is some research about all this. Thanks.

I think that historically most pipes were made of lead. However they were sometimes made of hollowed out timber. I think that the problem of the Roman ruling class was not just lead pipes, but cosmetioc uses of white lead (lead oxide). I do not think there is any problem with modern tins; if there is with fish, it must be coming from the water they swim in or the food they eat. Peterkingiron 22:51, 18 April 2006 (UTC)
Lead solder is no longer used in cans. It can leach out and poison people who eat the food. An expedition to find the Northwest Passage by John Franklin in 1845 is thought to have succumed to lead poisoning after eating only canned food (There is some dispute; see the article on Sir John Franklin). The bodies were found to contain high levels of lead. I have never heard of a problem with lead in fish; are you thinking of mercury?

[edit] Lead smelting

The present article says nothing about

  • how lead is smelted from its ore, either at present or historically. All I can see is an incomplete setction in Derbyshire lead mining history.
  • how silver (a valuable impurity in lead ores) is recovered in the course of smelting, either currently or hisotircally
  • other lead related industries, such as the production of white lead. Peterkingiron 22:34, 15 April 2006 (UTC)

Somebody's changed "smelt" back to "melt". I distinctly remember fixing that, but anonymous edits have been disabled (I can't be stuffed registering for Yet Another Bloody Website Account). Could somebody please change the sentence "It is highly malleable and ductile as well as easy to melt." to "... easy to smelt", as it should be? Ta. —The preceding unsigned comment was added by 130.194.11.64 (talk • contribs) .

Edit done, old protection lifted. Femto 14:36, 20 November 2006 (UTC)
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