Talk:Lead/Archive 1

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

WTF. Will someone please get rid of the image on the page. Vandalism. Goddamn. -DWRZ 02:05, 19 March 2007 (UTC)

Isotopes
This section seems wrong. The radiogenic Pb202 should be counted in the unstable istopes ? It would be nice to say what decay generates Pb202. Why does it claim there are only 3 unstable isotopes ? does it mean naturally occuring, or created artificially by some date long ago ? Rod57 (talk) 01:06, 23 May 2008 (UTC)

How is lead created?
Would someone please add a section showing how lead is actually created? I'm a lay person and all I gathered from this article is that lead "occurs naturally, but is rare." I would like some more information 69.138.74.116 (talk) 04:09, 17 March 2008 (UTC)
 * Most lead is produced from the mineral galena, lead sulfide. The statement that lead occurs rarely in nature means as pure, native lead. It is quite common in combination. Cheers Geologyguy (talk) 14:14, 17 March 2008 (UTC)

Fusion in stars made all the atoms up to Uranium. We dont have any reason to think that all the lead had to be made from decay of uranium. 202.92.40.8 (talk) 11:48, 28 December 2008 (UTC)

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 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)

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)

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)

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)

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 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.

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?

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)

I have a bit of a problem with the lead production section: It says (and this is supposedly referenced information) that during roasting the lead sulfide concentrate is converted to metallic lead. Lead concentrate roasting is an oxidative roast. PbS is converted primarily to PbO, and yes some amount of PbSO4 and lead silicates end up in the sinter. I say sinter, because the roasting is normally carried out in a travelling grate sintering machine. I was about to delete and correct the paragraph, but noticed that it's referenced. I don't have access to that (1949) reference. Can someone please check on this for me? I can counter reference my statements above, and I've been in a lead smelter and seen a Dwight-Lloyd sintering maching operating, preparing lead oxide sinter for blast furnace feed.BSMet94 20:21, 1 February 2007 (UTC)


 * I was the one who put that in about PbS roasting. The chemical reaction is documented in the next section. I will recheck the references tonight when I get home, but my recollection is that the quantity of lead metal that you get versus lead sulfate is depenent upon the amount of excess oxygen present. The Samans reference is indeed old, and perhaps modern lead smelting doesn't take advantage of this reaction anymore. I will quote the reference on this talk page and let you decide. Karl Hahn (T) (C) 22:02, 1 February 2007 (UTC)


 * On review of the Samans source, my-bad. I misinterpreted the list of sintering products. Inded, as BSMet94 has pointed out, the sintering is done with the objective of removing as much sulfur as possible, and hence is done with excess oxygen. The reactions list shown on page 250 does not show any metallic Pb as a product.


 * "The final sinter will contain about 52% lead [this is what I misinterpreted], 2% sulfur, 8% silica, 15% FeO, 3% lime and small amounts of other metals and oxides.


 * "Any of the following reactions may occor during roasting: [reaction list follows]"


 * I am going to fix the paragraph in the main article immediately. Karl Hahn (T) (C) 01:19, 2 February 2007 (UTC)

Good collaboration on that little topic! Thanks.BSMet94 04:42, 2 February 2007 (UTC)
 * I agree. However, we still need do with something on historical smelting processes, perhaps as a separate article.  I am surprised to read that modern smelting is in a 'blast' furnace.  18th and 19th century smelting was in a reverberatory furnace; when was the use of blast furnaces introduced?  The present blast furnace article is entirely about iron; if blast furnaces are being used for other metals, that article requires a further section.  Peterkingiron 12:45, 3 February 2007 (UTC)


 * I just reviewed the Samans reference again. It has a diagram of the blast furnace, which is a dwarf compared to its iron-smelting cousin. It also says "the lead blast furnace is similar in construction to the copper blast furnace." It goes into detail about temperature, charge, and operation, as well as a reaction list. Samans does not say when this process was adopted. The reverberatory furnace is used, according to Samans, for refining after smelting. BTW I just updated the article here to list a little more detail about the waste materials from the blast furnace process. Karl Hahn (T) (C) 14:22, 3 February 2007 (UTC)


 * Primary lead smelting is almost universally carried out in blast furnaces. They are a very different design of blast furnace than that used for ironmaking, but the principle of operation is the same.  I've seen one in operation.  There have been a few other smelting furnaces developed for lead (e.g. QSL, Kivcet), but they haven't really replaced the blast furnace.  To my knowledge lead smelting is not and has never been carried out on any notable scale in a reverberatory furnace, reverbs are used in refining for lead.  Your book is right in that the lead blast furnace is similar in design to the copper smelting variety, but copper blast furnaces went out of common use by the 1920s. BSMet94 05:20, 4 February 2007 (UTC)

Lead burning color
I see several Wiki metal articles (Zinc, etc.) mention you can test for the metal by burning a sample of it and viewing the colour of the flame produced.

Does anyone know the colour of flame when burning Lead? —The preceding unsigned comment was added by Quatermass (talk • contribs) 17:46, 27 December 2006 (UTC).


 * Some sort of whitish pale greenish blue, descriptions vary... See here for a spectrum. Femto 19:02, 27 December 2006 (UTC)


 * Flame test says pale green. RJFJR 18:06, 21 March 2007 (UTC)

Lead Should be hard as metal
Grown from the local gloucester boxing circuit Simon marcer grew up with the fighting name lead. He thought it was a sign of respect as "hard as Metal". But in fact his lack of knopwledge due to skiving chemistry at school meant he didnt see the irony that lead is the softest metal. —The preceding unsigned comment was added by Virtualwaster (talk • contribs) 10:24, 25 April 2007 (UTC).

Lead regulation
There should be a whole article about Lead regulation. Until then, all we seem to have are Lead poisoning and Restriction of Hazardous Substances Directive. The main Lead article does not give us figures on total global production/use; we don't know how it is changing annually, over decades. We have been using this known poison for thousands of years. In the US, lead plumbing is still in use, and we are so negligent as to use it to balance the wheels on our cars. How does Europe compare? What organizations are most active against lead hazards?-69.87.200.233 18:56, 4 September 2007 (UTC)


 * It took me about 10 minutes to identify a whole raft of sources on this topic at EPA:          , and so on. Also do a search on "lead pollution" or "lead production" or "heavy metal pollution" at  to find out what what's going on with lead regulation in Europe. Once you've done the research, please feel free to write some text in lead or create a new article for lead regulation. Please be sure to read and follow Help:Contents/Policies and guidelines when creating new text. Help:Contents/Editing Wikipedia will give you some useful info on how to edit. I also have a useful cheat-sheet at User:Karlhahn/usefulLinks. Karl Hahn (T) (C) 15:44, 5 September 2007 (UTC)

The regulation section of Lead poisoning should be big enough now to split off into an article. It is easy to find an overwhelming amount of material -- http://www.atsdr.cdc.gov/csem/lead/pb_standards2.html is a great place to start. But haven't found any non-US resources yet... And maybe there should be a redirect from Lead toxicity to Lead poisoning?-69.87.199.214 17:21, 9 September 2007 (UTC)

Production pollution
There must be pollution, danger, and toxicity associated with lead mining and production, currently. But there does not seem to be any info in WP about this. Please add such information.-69.87.203.198 11:57, 5 September 2007 (UTC)

Reasons for reverting pourbiax diagrams

 * 1) None of the recent additions by Cadmium (talk) are accompanied by any references whatsoever.
 * 2) Chemistry phase diagrams do not belong in the health effects section.
 * 3) It is not at all clear what the diagrams mean, especially the vertical "ESHE/V" axis. The pre-existing descriptive chemistry section was targeted at the level of understanding a reader might have after taking a typical high school chemistry class. Much of the new material is at the level of an undergraduate advanced inorganic chem class. WP is not an advanced inorganic chem textbook.
 * 4) Diagrams should be thumbnail size to the right of the text they illustrate. They should not be dominating the text. Readers who want a better look at a diagram will click on it.
 * 5) Lead sulfate diagram has horizontal axis showing concentration of HS– rather than HSO4– concentration.

A paragraph on lead (II) chloride complexes would certainly be a good addition. The graph is unnecessary though. All that is needed is text stating the existence of the complexes and the conditions under which they form. And it all needs have a reference. Karl Hahn (T) (C) 18:14, 23 September 2007 (UTC)
 * I would say, fork these sections directly into an own article, they are much too difficult for an entry level article like lead (I mean, the man in the street will type 'lead' to know more about the metal; this information is way to specialistic for this article). Hope this helps.  --Dirk Beetstra T  C 19:35, 24 September 2007 (UTC)
 * I think the diagrams and related information are somewhat useful, and even though they are a bit technical, I wouldn't prefer the complete removal of them. The question boils down to where the information would be best located.  Many of Karlhahn's objections can be addressed without removing the information from this article (such as lack of referencing, diagram size, HS– vs HSO4–etc.) Personally, I don't have an objection to having the diagrams in this article, but if others agree with Dirk that  a separate article would be better, and I'd be content with that too.  --Ed (Edgar181) 20:54, 24 September 2007 (UTC)

Additions testing and answer to Tannin
Former Analytical Chemist for test lab: environmental and industrial. 1. Usually analyze Lead via Atomic Absorption spectroscopy but occasionally by wet chem methods. Standard wet chem analysis of solder composition was PbFCl titration. Lead has a strong affinity for a single flouride, forming PbF+ which is titrated with Chloride (PbF2 is soluble). The dissociation constant for (PbF+)(Cl-) was on the order of Silver Chloride. Dithizone (1,5-Diphenyl-3-thiocarbazone) method (EPA sw846) for PPM determinations. http://www.woodrow.org/teachers/chemistry/1989/49heavy-metal.html see #4 for how Lead gets into fresh water shellfish. Today environmental Lead by Ion Coupled Plasma (or ICP). 2. Lead Oxide is used in Gold ore assays, much of the PbO subliming in the furnace. http://www.nbmg.unr.edu/comstockscience/fireassaying1.shtml 3. Study of children playing near major roads (High PbO and PbBr2 from combustion of leaded fuel, residue in dirt by roadside). Blood of kids with Parts Per Billion Lead had significant IQ lowering. The "biochemistry of lead poisoning" is an mechanism of gross lead poisoning in adults. The mental damage of heavy metals (Hg, Tl, Pb) in children is different. Interesting that the RoHS thing replaces Lead in solder with Silver which is actually more toxic in adults. 4. Pb3O4 is an oxidizer that was used to protect steel and iron, often used as paint on structural beams and ships (also barnacle protection).

5. to Tannin re: 204 - - -   rem  Earth is (theor.) 4.5E9 years old. see http://en.wikipedia.org/wiki/1_E17_s

20 years ago Pb204 was thought stable, but by rechecking previously previuosly considered stable isotopes with more sensitive instruments very long half lives can be detected. The standard surplus gas tube radiation detector that we had in high school science had a higher tick rate from backround (cosmic rays etc.)than from a sample of depleted Uranium (U238) 4.5E9 yr half-life.

As to differing half lives of isotope 204: I don't have my Chemical Rubber Handbook here, but I'm assuming your errant half life is synthetic Pb204m. The high energy ion bombardment that that is used to form isotopes may leave the isotope formed with excess energy above the ground state. Generally these metastable states emit the excess energy as a gamma photon hence Pb204m >> Pb204 + gamma.

6. add ref to http://en.wikipedia.org/wiki/Decay_chain page for origin of Lead isotopes

Shjacks45 04:44, 8 November 2007 (UTC)

Pencil Lead
This subject is discussed twice, both in the "Uses" and "Phrases" sections. Should it be consolidated? --Claygate (talk) 20:39, 22 June 2008 (UTC)
 * I removed the phrases section as it was just a trivia section that had no real justification for existence. Wizard191 (talk) 23:20, 29 June 2008 (UTC)

Lead mining in Wales
This section seems very out of place to me. It talks about a very specific occurrence of lead, whereas the rest of the occurrence section is much more general, which is they way I think it should be. Is there a different article where this would fit better? Or perhaps it should just be removed outright? Wizard191 (talk) 23:35, 29 June 2008 (UTC)
 * It does seem to lack Importance. I'll add the tag for the heck of it. Primalmoon (talk) 21:54, 16 August 2008 (UTC)
 * I think the right solution would be to fork this section into a separate article. The Derbyshire lead mining industry already has its own article, and I see no reason why there should not be others on other non-ferrous mining fields.  Peterkingiron (talk) 15:18, 31 August 2008 (UTC)
 * Sounds good to me! --Wizard191 (talk) 15:21, 31 August 2008 (UTC)

Can lead be handled with bare hands?
Can lead be handled with bare hands? I've just done that and my hands became dirty so I have washed them quite thoroughly with water, and now I'm worried. ... Rfwoolf (talk) 14:46, 31 August 2008 (UTC)
 * This is not a forum. Please don't use it as one. --Wizard191 (talk) 14:50, 31 August 2008 (UTC)
 * I am seeking information I expect to find in the article. Rfwoolf (talk) 14:54, 31 August 2008 (UTC)
 * If you are not satisfied with the content of the article add to it. Don't come to the talk page and ask a question on here as though this is a forum to make a point. That's gaming the system. --Wizard191 (talk) 14:59, 31 August 2008 (UTC)
 * Or if I don't have the knowledge to actually add to the article, I could point out what I find missing or unclear in the article on the talk page. If I knew whether or not lead could be handled with bare hands a) I wouldn't have asked, and b) I would have put it in the article. Rfwoolf (talk) 15:05, 31 August 2008 (UTC)
 * Wikipedia is only as good as what its editors add. If you would like something added you have two options: 1. research it and add the info, or, 2. ask on the talk page to have the info added. You didn't do either of these. You asked a specific question about the topic of the article, but didn't ask to have that info added to the article. The point here is to phrase your questions/inquires correctly. As a secondary point, peterkingiron points out that the proper place for this info to be added is the lead poisoning article. --Wizard191 (talk) 15:26, 31 August 2008 (UTC)
 * Wizard191 I am choosing to disengage with you as I find you too unreasonable. Perhaps we will have to agree to disagree. There are probably hundreds of entries on talkpages on wikipedia added every day of people asking questions and pointing out what is unclear or missing from articles. That is what I have done and Peterkingiron has been a star - a true Wikipedian for addressing the enquiry - and perhaps ultimately the requested information will one day find its way either into Lead or Lead poisoning. If you think the way I phrased my enquiry was wrong then perhaps you could have been a bit more diplomatic, acknowledging that the Talkpage is indeed the place to point out issues with an article but then adding that I should perhaps rephrase it into a slightly different format. Instead you have accused me of "making a point", "gaming the system", and (before changing it) threatened to even block me. My attempts to reason with you seem to indicate that you are the type who hates to retract their statements or admit any margin of error, mistake, or wrongdoing. In such cases I will defer to you, You win. I'm wrong. You're right. I will never ask questions on a talkpage ever again. Thanks peterkingiron Rfwoolf (talk) 15:48, 31 August 2008 (UTC)

It would be useful to have a section added to the lead poisoning article dealing with this issue. My understanding (but without certain knowledge) is that handling clean lead is probably harmless. If the "dirt" was actually corroded lead, you need to take steps to ensure that you do not ingest it, such as thoroughly washing your hands (not merely rinsing them). However, I am not an expert and my advice may be unreliable. Peterkingiron (talk) 15:15, 31 August 2008 (UTC)


 * Disclaimer: what follows is not Medical Advice™, blah, blah, blah... That said: Rwoolf, don't worry, you won't get acute lead poisoning just from touching lead once. As for chronic poisoning, that's more likely to result from repeated exposure over long periods of time. So, if you handle lead every day, it would be a good precaution to wear gloves, have proper ventilation, etc. Washing your hands thoroughly after handling lead is also a good idea. To Wizard191, I can only suggest reviewing WP:BITE. Articles are very often improved thanks to the questions that people post on the talk pages, because such question can highlight omissions or lack of clarity. One final comment, however (to no one in particular): It is Wikipedia policy not to offer medical or practical advice, and there is consensus that Wikipedia is not an MSDS (material safety data sheet). Therefore whatever information is added to the article regarding Rwoolf's question must be tempered by these considerations. --Itub (talk) 09:15, 1 September 2008 (UTC)
 * Thanks for the input guys. Not that I handle it often I will now buy some gloves and a mask. I washed my hands about 2 times and shortly afterwards I showered, too, but was still a bit worried. :) Rfwoolf (talk) 15:45, 2 September 2008 (UTC)

I think it is important to include information on the health effects of lead in this article as well. Lead poisoning is a specific disorder, and that is very distinct from the subclinical effects of lead. —Preceding unsigned comment added by 99.240.79.165 (talk) 11:13, 16 January 2009 (UTC)

Problem with exhaustion of lead supply cite
The citation entitled "How Long Will It Last?", supposedly backing the fact that lead supplies will run out in 42 years, doesn't seem to actually contain this information. The link to the article online is here:

http://environment.newscientist.com/channel/earth/mg19426051.200-earths-natural-wealth-an-audit.html

No info on the 18 years figure either. I'm concerned, because it would seem that if lead supplies are really so short, we would be seeing much broader recycling efforts, since lead production must start declining far before supplies are exhausted. More likely, I would imagine that the 42 year figure refers to the date where lead production will peak. —Preceding unsigned comment added by Zooberman (talk • contribs) 19:11, 23 September 2008 (UTC)


 * That source does state that it will run out in 42 year. It's in the third diagram on the right. That diagram also notes that 70% of lead is recycled. --Wizard191 (talk) 19:39, 23 September 2008 (UTC)

Check this diff please
Some content was removed. Should it be restored? Crystal whacker (talk) 18:18, 28 December 2008 (UTC)
 * Yeah, the supposed ref he gave for some of his edits was bogus. I reverted them as such. Wizard191 (talk) 21:56, 28 December 2008 (UTC)

Assessment comment
Substituted at 15:14, 1 May 2016 (UTC)

Use as a radiation shield
I noticed the section about lead's uses does not mention its widespread use as a radiation shield. All I see is one image of lead bricks with a caption saying they are used for this purpose. I think this common use deserves a dedicated paragraph in the Applications -> Elemental Form section. Ericobnn (talk) 15:04, 12 December 2013 (UTC)

Units for Density
I don't think the units for density for any of the elements are correct. Density is mass PER unit volume. the "per" means "/" not "•". eg. ρPb = 11.34 g/cm³.

Maybe the "g•cm³" is a different way to write it, but I think it is confusing. Someone should fix that.

--Drew.wollman 16:22, 6 September 2007 (UTC)


 * Observe that the actual rendering is g•cm−3, which is correct (because of the minus sign in the exponent. Karl Hahn (T) (C) 17:04, 6 September 2007 (UTC)


 * Your right. I totally spaced the "-".--Drew.wollman 23:07, 7 September 2007 (UTC)

On the Lead page one of the density values is listed as: 11.34 g*m3 both the unit "m" is wrong (should be cm) and the exponent "3" is wrong (should be -3) I think it should be: 11.34 g*cm-3 —Preceding unsigned comment added by 70.101.74.40 (talk) 16:42, 11 April 2009 (UTC)


 * It appears correct right now. Wizard191 (talk) 20:30, 11 April 2009 (UTC)


 * Who decided it was a good idea to use the CGS system? This is the 21st century, let's get with the MKS style units. 66.206.229.112 (talk) 13:19, 7 July 2009 (UTC)
 * The figures are identical to specific gravity. The reason for using these is that they come out as small numbers: water is 1, but you can express them as tonnes per cumbic metre, if you prefer - the figures will be the same.  MKS would require the inclusion of a factor of 103.  Not so stupid as you thought! Peterkingiron (talk) 16:54, 8 July 2009 (UTC)

The use of "Specific heat capacity is incorrect as it is the Molar heat capacity which is given. —Preceding unsigned comment added by 131.247.38.61 (talk) 22:21, 19 October 2010 (UTC)

The two comments about Pb or Pb-208 being the "heaviest" non-radioactive element/isotope don't make any sense. The weight (heaviness) of something in a fixed gravitic acceleration is determined by the mass of the item. Presumably what is meant is that Pb has the highest atomic number of any stable element. Many other elements (Au, W, Pt, etc.) have higher densities than Pb. 2601:8:9680:FE:8110:B098:5190:90FD (talk) 19:50, 8 June 2015 (UTC)

Old word for lead
I've been told that lumb is an old word for lead. As a diver I see crates containing lead weight posted lumb for sale but yet there's no mention of it in reference or dictionary links. 87.85.229.34 (talk) 12:40, 17 March 2009 (UTC)Belinda Gadsby
 * Who told you that? "Lumb weights" are made of lead, but so called because produced by Lumb Brothers. William Avery (talk) 12:53, 17 March 2009 (UTC)
 * I think that what you have picked up is "plumb" -- this is a version of the Latin plumbum. The word occurs for example in plumbline.  However that is indicated in the first line of the article, so that no change is needed.  Peterkingiron (talk) 23:36, 17 March 2009 (UTC)

Pencils
I added a bit to the section about pencil lead. The article cited actually contradicted the "pencils never contained lead" statement because the Roman pencil was actually made of solid lead. The wooden covering was an innovation to accommodate the use of more fragile graphite, which is preferred to lead because it leaves a darker mark. (Maybe I should add that to the article too?) Paddingtonjbear (talk) 00:28, 5 December 2009 (UTC)
 * Thank you. IMO, this will do for the lead article, which shouldn't really focus on the history of pencils. Yes, early writing tools were made of lead, but IMO, "stylus" is a more appropriate modern term for those rather than "pencil". Materialscientist (talk) 00:31, 5 December 2009 (UTC)

Pencils doesn't include lead, they include carbon.58.187.90.251 (talk) 11:29, 14 March 2010 (UTC)


 * Why not mention of it being added to cigarettes? —Preceding unsigned comment added by 67.191.105.235 (talk) 06:59, 26 January 2010 (UTC)

kkok —Preceding unsigned comment added by 68.81.116.98 (talk) 00:53, 25 April 2011 (UTC)

This section needs a little reworking.
 * Why Pencil “Lead” is Called “Lead”
 * Pencil History

Radioactive
Radioactive elements start on polonium or lead?58.187.90.251 (talk) 11:29, 14 March 2010 (UTC)
 * Lead is nonradioactive, bismuth is extremely weakly radioactive, and polonium is radioactive. All elements past bismuth (for practical purposes) are radioactive. --Chemicalinterest (talk) 11:39, 12 May 2010 (UTC)
 * All isotopes of Bismuth (and any other element with a higher atomic number than lead) are considered to be radioactive; therefore Lead has the highest atomic number of all stable elements an can be considered the last (so to say) of the stable elements. I do not believe that that fact is in the article and I think it would be both informative and interesting to include it. --Ham Radio 23:22, 14 September 2011 (UTC)

Especially as the bismuth entry specifically says bismuth's most stable isotope is slightly radioactive with a halt live much greater than the age of the universe, and lead is the element with a highest atomic number with a stable isotope. This seems more relevant to mention in the lead entry than the bismuth one - or both! Holland jon (talk) 22:28, 27 August 2013 (UTC)
 * From the article (bolding is mine):


 * Lead occurs naturally on Earth exclusively in the form of four isotopes: lead-204, -206, -207, and -208. All four can be radioactive as the hypothetical alpha decay of any would be exothermic, but the lower half-life limit has been put only for lead-204: over 1.4×10^17 years.


 * (1) This is equivocal. Are these isotopes stable or not? You can't tell from these statements.
 * (2) Users Chemicalinterest and Ham Radio say that lead is the last stable element, and many overview charts and simple summaries say that lead is stable and bismuth is not.
 * (3) The statements presented here are not explained or amplified in Isotopes_of_lead. There, the four isotopes are called stable, with only summary remarks in the footnotes. The two articles ought to agree exactly, or the more specialized one should be more precise. If lead is stable, say it. If there are some subtleties or it is not known, that should be explained. After all, these isotopes are the most prevalent -- they deserve more than these cryptic remarks. 178.38.157.66 (talk) 13:32, 23 November 2014 (UTC)


 * Lead is observationally stable. It is expected to undergo radioactive decay, but this has never been seen, so the half-life must be incredibly long. This is true for all elements with atomic number over 40. I've changed it to a short sentence Lead occurs naturally on Earth exclusively in the form of four observationally stable isotopes: lead-204, -206, -207, and -208. All four could theoretically undergo alpha decay with release of energy, but this has not been observed for any of them." 204Pb has been theoretically expected to have a half-life over 1.4×1017 a, but I cut this from the paragraph as it is already stated in the infobox. Double sharp (talk) 13:47, 23 November 2014 (UTC)

Lead wool
I started an article on lead wool (perhaps named by analogy to steel wool), thin strands of lead used to cold-caulk pipe joints. This seems to have been introduced around 1900 and to have stopped being manufactured around 1980 (educated guesses based on the limited information I could find about two companies with "Lead Wool" in their names. Anyone who can improve that article is encouraged to do so. Eastmain (talk • contribs) 03:10, 30 March 2010 (UTC)

Ductile?
Under section 1) Characteristics: This section states that a property of lead is that it is ductile. When one follows the ductile hyperlink it is redirected to Ductility. The Ductility section explains by example that "gold is both ductile and malleable, but lead is only malleable". There is a correction or explanation needed to one of these pages or the other by someone who is qualified on the subject matter. Elkfla (talk) 02:53, 12 May 2010 (UTC)
 * Google book search reveals both statements, i.e. lead is malleable and ductile and lead is malleable but not ductile. Second are mostly copied from wikipedia :-). The Characteristics section here comes from the CRC handbook .. To me, the answer is both terms are subjective (like what is "soft") and lead is reasonably ductile. Materialscientist (talk) 03:38, 12 May 2010 (UTC)
 * Malleability is flexibility and softness, while ductility is the ability to be drawn into wires (lead wires?) --Chemicalinterest (talk) 11:40, 12 May 2010 (UTC)

Use in nuclear physics reasearch
Lead 208 ion particle beams are used in the Large Hadron Collider (LHC) particle accelerator at CERN to study high energy collisions of massive subatomic particles. This research is partly intended to better understand the nature of subatomic matter by producing high enough energy densities to produce massive sub atomic particles such as the theorized Higgs boson. The large nuclear mass of lead makes it suitable for this use.

Would someone with editing privilage please add the "Use in nuclear physics reasearch" above to the lead wiki as it is a technologically significant use of lead. Thank you. A Wikipedia user. —Preceding unsigned comment added by 12.75.134.164 (talk) 06:57, 1 October 2010 (UTC)
 * No, that would be too detailed for a general article. Peterkingiron (talk) 20:04, 29 October 2010 (UTC)
 * and there is an apparent contradiction between "nuclear physics reasearch" and "technologically significant use". Materialscientist (talk) 22:29, 29 October 2010 (UTC)

need more details about epa refusing to ban lead
can the article expand more on that subject, with more in depth details about what happened and what the epa said exactly?

can the article discuss more about who mines/manufactures lead and what companies profit from keeping toxic elements like lead in main stream uses,rather than using safer alternatives, like for manufacture of bullets. —Preceding unsigned comment added by 98.160.131.17 (talk) 00:30, 20 October 2010 (UTC)


 * Companies use lead for bullets mostly for safety and reliability. (Not for profit, otherwise they'd have abandoned it long ago.) Bullets for rifled weapons can be copper or uranium clad but dangerous issues may arise when projectiles of other materials are used. Lightweight materials (magnesium, aluminum and all transition metals lighter than molybdenum) lack the inertia needed for accuracy. Tungsten is to brittle to leave the barrel in one piece. Gold is too soft (and expensive). Radiological materials are more hazardous than lead. Silver is expensive and may corrode in storage to a greater extent than lead. No methods exist for the mass production of bullets from refractory metals.


 * Shot for non-rifled weapons (shotguns) may be made from alternative materials like steel but accuracy is diminished. This is good enough for bird hunting but is unsuitable for riot control.


 * Refining of copper, gold, nickel and zinc are not enough to sate the high demand for silver which can also be won from mined lead ore.


 * There are still many industrial processes that require lead for witch there is no substitute. Release of lead into the environment from industry is decreasing while steps to prevent release are becoming more common. Increased knowledge of the hazards of lead have lead to better safety measures for those who work with it. Many companies are voluntarily moving toward lead-free products including solder and fishing weights. The delay in this move by some companies is due mostly to the investment needed in retooling the production line. Even in the absence of government regulation consumer pressure will drive these companies to go lead-free where possible within the next five to ten years. JTTyler (talk) 04:40, 29 October 2010 (UTC)
 * I think our unlogged-in contributor wants an article on lead pollution and lead manufactures or the uses of lead. Such articles might be useful, but this is a general article on the element lead and should not be cluttered up with excessive detail.  Issues as to which companies profit most from lead sound to me like an invitation to WP:ATTACK, which we do not allow.  Furthermore, they are liable to have WP:RS difficulties, though not insurmountable ones.  Peterkingiron (talk) 20:02, 29 October 2010 (UTC)

Lead In Bones And Circumstances Under Which Lead Reenters Bones
Some of the lead can stay in your bones for decades; however, some lead can leave your bones and reenter your blood and organs under certain circumstances (e.g., during pregnancy and periods of breast feeding, after a bone is broken, and during advancing age). In adults, about 94% of the total amount of lead in the body is contained in the bones and teeth. About 73% of the lead in children's bodies is stored in their bones. Referenced from ATSDR on January 22, 2011. 72.196.107.224 (talk) 21:27, 22 January 2011 (UTC)Samantha Mosias

Same ref name used on two different references
This article contains two different references with the same name:

Since the article also contains, I'm not sure how to clean this up. Could someone who is familiar with these references fix this issue? (Thanks to User:Redrose64, who discovered this issue in response to a question I posted here.) GoingBatty (talk) 17:02, 2 October 2011 (UTC)
 * Thanks Stone for fixing this issue! GoingBatty (talk) 20:19, 2 October 2011 (UTC)

Alchemy Reference
Please could we have a citation for the comment "In alchemy, lead was thought to be the oldest metal" Thanks Moebius999 (talk) 10:53, 11 January 2012 (UTC)

Archieved info
here--R8R Gtrs (talk) 15:41, 25 March 2012 (UTC)


 * I've created Compounds of lead. Try to move all the stuff that was deleted there. Nergaal (talk) 20:05, 7 April 2012 (UTC)

Typo in Organolead Section

 * I know the page is protected, so I can't change it yet. Could someone fix the typo in the Organolead section? I think bong should be bond.

Erjablow (talk) 03:13, 16 May 2012 (UTC)
 * Fixed, thanks. Materialscientist (talk) 03:25, 16 May 2012 (UTC)

The Romans and Lead
In the paragraph about the Romans, the word "Roman" appears twice in the same sentence. It would be nice if the title of the link to "Roman Britain" could be changed to just "Britain": ''The largest preindustrial producer of lead was the Roman economy, with an estimated output per annum of 80,000 t, which was typically won as a by-product of extensive silver smelting. Roman mining activities occurred in Central Europe, Roman Britain, the Balkans, Greece, Asia Minor; Hispania alone accounted for 40% of world production.'' 193.60.63.224 (talk) 08:44, 18 May 2012 (UTC)

I personally wouldn't. I don't know how islanders think, but from the depth of the continent the term is more like trying to collect what is now England and Wales (no Scotland). Like using "Korea" for "South Korea"--R8R Gtrs (talk) 18:16, 18 May 2012 (UTC)

Perhaps you misunderstood my point. What would you think if the text read thus: Roman mining activities occurred in Roman Central Europe, Roman Britain, the Roman Balkans, Roman Greece, Roman Asia Minor; Roman Hispania ... 193.60.63.224 (talk) 09:48, 21 May 2012 (UTC)


 * The Roman Balkans, Roman Greece, Roman Asia Minor; Roman Hispania are identical because all Balkans, Greece, Asia Minor, Hispania were occupied by Romans. Roman Britain is only the south while the north was non-Roman Britain.--Stone (talk) 21:39, 21 May 2012 (UTC)

Do you think it possible that Roman mining activities could take place in non-Roman Britain? I stick by my original suggestion! 193.60.63.224 (talk) 10:52, 22 May 2012 (UTC)


 * There is Chinese oil drilling in non-Chinese Africa. There is German forest and wood production in non-German Austria. As compensation for Austrian Saltmining in non-Austrian Germany.--Stone (talk) 12:25, 22 May 2012 (UTC)

suggestions
The graph of production is a wonderful figure and should be displayed large and centered.

Cut the number of Roman lead photos to one. (Lots of images is good, but don't have 3 of the same thing...find other aspects of the article to illustrate.)

Show (and discuss) lead chloride precipitate as an analytical test for lead ions in water. I don't see a good free picture...but get some Wikichemist to make one for you. (A cloudy test tube...or even more spectacular if you can show addition of reagent creating the preciptation.)

Research and add a couple more sentences on tetrathyl lead as a former application.

69.255.27.249 (talk) 00:20, 17 June 2012 (UTC)

Electronegativity
I saw on my school books that the value of lead electronegativity is different depending on th book. I argued with another wikipedian on it.Wikipedia and we compared nine books, four Wikipedias (en. de. fr. & it.) and an encyclopedia. The resulting value was 1,8 (Pauling's scale) and 2,33 is the electronegativity of lead(II) ions. I changed this date from 2,33 to 1,8 in it.Wikipedia, what about en.Wikipedia?

The original discussion is here (in italian). Bokuwa (talk) 10:49, 8 September 2012 (UTC)
 * Nearly a year late, but changed to 1.87 here. Double sharp (talk) 15:53, 26 August 2013 (UTC)

File:Lead electrolytic and 1cm3 cube.jpg to appear as POTD soon
Hello! This is a note to let the editors of this article know that File:Lead electrolytic and 1cm3 cube.jpg will be appearing as picture of the day on October 19, 2012. You can view and edit the POTD blurb at Template:POTD/2012-10-19. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page so Wikipedia doesn't look bad. :) Thanks! — howcheng  {chat} 17:26, 17 October 2012 (UTC)

Spelling Correction
I think that the third sentence in the first paragraph should be "It is considered by many to be a heavy metal." instead of "It is considered by many to be a heavy metals." Xin-Xin W. (talk) 01:16, 3 December 2012 (UTC)
 * Done, thanks. Vsmith (talk) 01:28, 3 December 2012 (UTC)

Edit request on 27 August 2013
The article on lead is missing 'symptoms of lead poisoning'.

92.21.194.214 (talk) 05:56, 27 August 2013 (UTC)
 * ❌: This is more relevant to the lead poisoning article itself, where the symptoms are already are. Double sharp (talk) 10:45, 27 August 2013 (UTC)

Oxides and sulfides section
This section contains a sentence that reads "Lead monosulfide is almost insoluble in water, weak acids, and (NH4)2S/(NH4)2S2 solution is the key for separation of lead from analytical groups I to III ions, tin, arsenic, and antimony." This doesn't make sense grammatically - what is it trying to say? Could someone clarify it? I would do it myself but I can't work it out. PaAt-56 (talk) 19:46, 4 October 2014 (UTC)

I think I've worked it out - is it trying to say "Lead monosulfide is almost insoluble in water and weak acids, and so use of (NH4)2S/(NH4)2S2 solution is the key to separation of lead from analytical groups I to III ions, tin, arsenic, and antimony."? If so, is this statement true? - and is it too much detail for the article? PaAt-56 (talk) 10:53, 5 October 2014 (UTC)

Now edited to remove excessive detail and add a citation. PaAt-56 (talk) 15:15, 14 October 2014 (UTC)

Effects upon cognition
Study reviewing bad cognitive effects of even very small amounts of lead: [] Linked from this article: [] 92.24.137.12 (talk) 17:08, 12 October 2014 (UTC)

Reactivity of lead with sulfuric acid
Leads reactivity with sulfuric acid seems to be overstated. Lead lined tanks/barrels were once, maybe even still, used for transportation of sulfuric- Rochow and Abel in their monograph on Silicon, Germanium and Lead say that only anhydrous sulfuric attacks lead at normal temperatures, insoluble lead sulfate passivates the surface. Transportation guidelines for shipping specified lead lined containers for sulfuric acid strengths less than 65%. Axiosaurus (talk) 18:36, 24 January 2015 (UTC)

Edit request: Distinguishing Organic and Inorganic Lead
Can the distinction be made clearer between these two categories of lead compounds? This is slightly cleared in the Lead Poisoning article []

Review
This section is dedicated to establishing a plan to improve this article, section by section. Double sharp and I will write the plan; everyone else is very welcome to add comments.

we need some general guideline on whether we should use compound names like "lead(II) oxide" or "lead monoxide"
 * MOS:CHEM says "Stock nomenclature (e.g. iron(III) chloride): there should be no space between the words and the oxidation state in parentheses (between "iron" and (III)). The oxidation numbers are stated only for cations, not for anions. Where the oxidation number is obvious (i.e. group 1 or group 2 metals), it is not included. Compounds with a substantial degree of covalency do not use Stock nomenclature." Double sharp (talk) 15:55, 21 August 2015 (UTC)

Maybe it's just me, but I feel I write better when I have some sort of model to follow the outlines of; probably Zn is the most similar FA in terms of history and Ge the most similar in terms of chemistry. Double sharp (talk) 15:55, 21 August 2015 (UTC)

lead
I want to write comments on this section after every other section has been discussed. But for now, I can't escape the feeling we shouldn't mention how Pb-208 is double magic and thus the heaviest stable nuclide of all: according to the current theory, it should be actually very slightly unstable, but in that case, we also have the ordinary magic Bi-209 with very little instability
 * Not sure about how to mention the magic thing. On the one hand we have Sn-100 and Sn-132 which are doubly magic and are not stable by any stretch of the imagination (just significantly more stable than their neighbours). And on the other hand according to theory there are no stable isotopes past Zr-92 anyway (Dy-164 if you don't count SF), and both of these are not really close to magic numbers. I think what is going on is maybe that Pb-208 would be like Bi-209 if not for the double magicity, which boosts its half-life by another few orders of magnitude? (Like how Ca-48 is stabilized.) But that's a bit complicated. So maybe we ought to just present the two facts "double magic" and "heaviest stable nuclide" as two separate things? Double sharp (talk) 12:28, 13 August 2015 (UTC)
 * I completely agree these facts should be treated separately. I'm not even sure we should mention the former (or even the latter) fact in the lead. However, of course, both will be added to the Isotopes subsection.--R8R (talk) 13:03, 13 August 2015 (UTC)

Characteristics
Looks more or less ok to me, but I can't escape the feeling we may need more data

This thing needs a copyedit so obviously :(

Bulk
Where do the carbonates and hydrocarbonates come from? CO2 in the air? All the compounds that cause lead to tarnish, do they all come from the air?

Atomic
I can't find a thing we're obviosuly missing. DS, if you see anything we're lacking, let me know

Upd: Okay, we're lacking a couple of sentences on ionization energies and elecronegativity
 * Uh yeah, we ought to mention that Sn and Pb have similar ionization energies because of the filled 4f subshell in Pb. Double sharp (talk) 16:10, 21 August 2015 (UTC)

Powdered lead burns... -- from this moment on, does the text belong to this subsection? Should it be moved to the Chemical subsection?
 * Yeah, I think so. That's where Greenwood & Earnshaw put it, under "Chemical reactivity and group trends". Double sharp (talk) 16:10, 21 August 2015 (UTC)

Explain pyrophoritciy in a couple of words?

Isotopes
pb-210 is a trace isotope, so the assumption lead only exists in form of its stable isotopes is false
 * Well, yeah, 210Pb is useful as a radioactive tracer, and works as a short-term dating tool. (ref) It's probably the most important radioisotope. I do note, though, that 209Pb, 211Pb, 212Pb, and 214Pb are also trace radioisotopes, so that alone wouldn't grant it a place: it's the long half-life and usefulness that does it, for me. Double sharp (talk) 16:12, 21 August 2015 (UTC)
 * BTW, cool fact: 205Pb decays into 205Tl, but fully ionized 205Tl bound-state beta decays into 205Pb! In fact 205Pb82+ is stable! (ref) Double sharp (talk) 16:16, 21 August 2015 (UTC)

Chemical
Merge paras 1 and 2

Does lead react with water in no oxygen is present?


 * Also, catenation is rather important for Ge, Sn, and Pb, though obviously not anywhere near as much as for C and Si. Double sharp (talk) 15:35, 2 November 2015 (UTC)

Compounds
In general, it seems a little wrong to use this format of the Compounds section. It goes into such detail for individual compounds, it's so different than how it was for fluorine. In general, it seems to me we should discuss more about lead itself (in compounds), than the compounds. DS (and anyone), could please re-assure me this format is correct or agree we need a change here?

What we're certainly missing is a subsection dedicated to oxidation states and behavior of lead ions when a lead salt is dissolved

An idea is growing on me we should create a common Inorganic subsection, where we would focus on lead ions and general properties of lead slats, with some material possibly standing out


 * Actually I don't see the problem with going into detail on some major compounds like we do now: we can keep that stuff and improve it. But I think we should add a preliminary going into this section, where we focus on Pb itself – that is actually a really cool idea. Then you can mention the key atomic traits of Pb that define its chemical personality, so to speak: and then a note on Pb(II) vs. Pb(IV). Oh wait, that is already in characteristics. But it fits better down there seguing into compounds, honestly. In fact, one thing's been bugging me for a while regarding Wikipedia element article organization – why on earth is chemistry usually kept away from compounds? It's hard to understand the compounds without knowing the element's personality. Double sharp (talk) 16:25, 21 August 2015 (UTC)


 * Okay, maybe... but then, I'll need a second opinion to be confident things are going right when we're actually starting to work on this one.
 * It's not "chemistry," it's just reactivity... so the whole Characteristics section is dedicated to the pure element. I got this feeling. Anyway, we're not actually restricted to the current format. We can combine the two. No one will punish us and the chances to get the bronze star won't be reduced. We'll see.--R8R (talk) 22:52, 2 September 2015 (UTC)


 * See Zinc, it represents exactly what I have in mind. This does seem to be better than going into detail for specific compounds to me.--R8R (talk) 14:36, 12 September 2015 (UTC)

One more thing, though: Pb(II) is more stable than Pb(IV), but organolead compounds are almost all Pb(IV) for some reason. Double sharp (talk) 15:34, 2 November 2015 (UTC)


 * great one, thanks--R8R (talk) 22:23, 5 November 2015 (UTC)

Need to add info about Pb2+ in solutions and properties of lead(II) ions in general, rework reactivity and organolead, and it should be good enough to start adding refs and missing figs--R8R (talk) 22:23, 5 November 2015 (UTC)

At the moment, I think we should be okay with this section. , pleasae, provide some feedback.--R8R (talk) 21:36, 9 November 2015 (UTC)

Oxides and sulfides
(Assuming the format and content will be retained)

So A-PbO and B-PbO are cubic and cuboidic?

B-PbO needs impurities to exist? Wow

We may just say PbO2 needs strong oxidizers in order to be obtained

hydroxyplumbates -- ew

Also, is it the same thing as the "plumbites" introduced in the previous para?

Will the reaction still be needed if we change the format?


 * There are more than 3 lead oxides: there's also monoclinic dark-brown/black Pb12O19, Pb12O7, and a jumble of non-stoichiometric messes between PbO1.42 and PbO1.57. Not really important compounds, but it forces us to skirt around giving an exact count. Double sharp (talk) 16:28, 21 August 2015 (UTC)

P.S. We could do with a brief mention of the instability of Pb(OH)2 – PbII does not really want to form simple hydroxides. That is more for the proposed lead-in covering Pb in solution. Of course Pb(OH)4 is unknown. With regard to heavier chalcogenides, PbSe and PbTe do have one interesting property: the colour gets muted as the molecular weight goes up. PbS is black, PbSe is grey, and PbTe is white. PbPo occurs in nature, as Pb is the daughter of all natural Po isotopes. Double sharp (talk) 16:34, 21 August 2015 (UTC)

Halides and other salts
Do we really want to tell our readers boring trivial stuff on how to obtain the difluoride? Listing its properties would be a better idea
 * Agree. Properties are more interesting to the average reader (especially colour etc.). Double sharp (talk) 16:34, 21 August 2015 (UTC)

What's lead hydrofluoride? Pb2+H-F-? Question solved, it is PbF2 * 2.5HF

Coordination number -- not only chemists will read this article, we can explain this without using such complicated terms


 * Um why not mention the appearance of the tetrachloride (yellow oil, stable below 0°C)? Also according to Greenwood 2nd edition (more recent than our current reference) PbBr4 is now known, but is laughably unstable, and it's PbI4 whose existence is doubtful (not surprising really, as TlI3 contains instead of I−). Coordination markedly increases the stability (e.g. M2PbCl6 are stable yellow salts, M = Na, K, Rb, Cs, ). Double sharp (talk) 16:25, 21 August 2015 (UTC)

Others
No mention of plumbane and its instability? Gives you a free one to tie in to the trend down group 14. You can also reinforce this thread to the reader by mentioning the stability order for halides: PbX2 > PbX4, and CX2 << SiX2 < GeX2 < SnX2 < PbX2. The trend down group 14 is particularly important for Pb after all, being the heaviest useful member of the group. Double sharp (talk) 16:26, 21 August 2015 (UTC)

Seriously no mention of metal clusters and the polyplumbide cluster ions? Double sharp (talk) 16:35, 21 August 2015 (UTC)

History
we may leave Theoderic out, I guess? (who is that, you may ask if you're not all that into Roman history) or we may use dates instead of names for specifying time periods

the graph is not a correct representation of what is given in the source, it doesn't show info for every century

"Further evidence of the threat lead posed to a human organisms..." - this is the first sentence in the last paragraph of the History section; needs to be corrected. — Preceding unsigned comment added by 68.231.112.193 (talk) 06:58, 21 April 2016 (UTC)


 * Sorry for such a late reaction; thanks for the notification.--R8R (talk) 09:22, 29 April 2016 (UTC)

Occurrence
(First of all, this section should be split to a subsection of Characteristics, named Occurrence (based on the content before the subheaders), and the rest of this section should become a separate Production section)

how many ppm in space/on Earth/in soil/in seawater? how much Pb in absolute numbers?
 * Quite a lot in the crust. It's really abundant for an element this heavy, and only Th and U come close. But we do need stats... Double sharp (talk) 16:39, 21 August 2015 (UTC)
 * Greenwood and Earnshaw give lead at 13 ppm, Tl at 8.1 ppm, and U at 2.3 ppm. Quite obviously this is because 206,207,208Pb (apologies for the notation abuse!) are the stable endpoints of the natural decay chains. This also means that the atomic weight is very variable and can only be quoted to 1 decimal place of precision (207.2). Double sharp (talk) 15:32, 2 November 2015 (UTC)

say how Pb is a chalcophile (actually, give zinc a look when writing this)

Production
(this subheader is for the info that will form the new Production section)

in 42 years -- as of when?
 * It's a 2007 article, so I would assume as of 2007. But why not work it out to 2049, since otherwise it'll get out of date? Double sharp (talk) 16:36, 21 August 2015 (UTC)

18 years --- same
 * 2006 + 18 = 2024, presumably. Double sharp (talk) 16:36, 21 August 2015 (UTC)

Ancient lead special use -- belongs elsewhere, possibly to Applications

(seems good in general on my first look)

Applications
It does not have the weight-to-volume ratio of many heavy metals, but its low cost increases its use in these and other applications. -- move one para up

we certainly don't need the cathode and anode reactions!

Lead, or sheet-lead -- what's the difference? is the latter just an industry-specific name for lead?

If we don't add any further mentionings of polyvinyl chloride, then we won't need the "(PVC)"

(In general, this looks good, except for some random para breaks, but we'll need to check some literature anyway)

Health
How much Pb will kill you?

"1 μg/g" or "10−5 relative"?

The component limit of lead (1.0 μg/g) is a test benchmark for pharmaceuticals, representing the maximum daily intake an individual should have -- move up the para


 * Honestly it might have to be "Precautions" instead as a header – finely divided Pb powder is pyrophoric. You don't see this in bulk obviously, because it forms a thin protective layer of insoluble oxide, oxocarbonate, sulfate, or chloride (depending on what is around – this is why Pb is often used to handle hot concentrated sulfurc acid). Double sharp (talk) 15:33, 2 November 2015 (UTC)

Vapor pressure wrong/inaccurate

 * Boiling point 	2022 K (101325 Pa?)
 * Vapor pressure 2027 K  100,000 Pa

Something is wrong here. Darsie42 (talk) 22:21, 1 November 2015 (UTC)
 * CRC 84th edition gives 1754 °C = 2027 K for Pb at 100 kPa, just like the article. But Zhang et al. give 2017 K for the boiling point? Double sharp (talk) 08:52, 2 November 2015 (UTC)

Pb electronegativity
The reason is that for Tl and Pb, electronegativity actually changes significantly with the oxidation state. Taking the more stable Pb(II) gives the 1.87 value that nicely conforms to periodic trends; taking the less stable Pb(IV) gives the 2.33 value. Double sharp (talk) 03:35, 13 November 2015 (UTC)

Mmm, yeah, I completely forgot about that :) thanks! I'll rework that sometime later--R8R (talk) 13:25, 13 November 2015 (UTC)

Half-life limits
Our infobox lists some half-life experimental limitations for stable isotopes; where do they come from?--R8R (talk) 14:25, 18 November 2015 (UTC)
 * From the isotope pages, where they were added (by XinaNicole, IIRC) with a lot of other material from the Universal Nuclide Chart. Double sharp (talk) 14:47, 18 November 2015 (UTC)


 * Okay; thanks.--R8R (talk) 05:55, 20 November 2015 (UTC)

Bulk
Double sharp, please help me with a second opinion. What do we need to improve in the current Bulk section properties?--R8R (talk) 16:34, 23 November 2015 (UTC)
 * Actually, I think it looks fine now – or at least I can't at first glance notice anything that may have been overlooked. If I find something new, of course, I will write about it here and add it to the article accordingly. Double sharp (talk) 12:43, 28 November 2015 (UTC)

Occurrence data
WebElements does have it, but this figures need a better backup -- http://www.webelements.com/lead/geology.html --R8R (talk) 10:44, 3 December 2015 (UTC)
 * Abundances of the elements (data page)? Double sharp (talk) 13:53, 3 December 2015 (UTC)
 * Oooh, I didn't know we had a data page for that. Thanks!--R8R (talk) 16:26, 3 December 2015 (UTC)
 * Mmm, on having a second look, I notice the list doesn't list any occurrence in the universe/etc. in ppb, only relative to silicon. As such, I think it's still worth it to find a better backup for the figs seen at WebElements.-R8R (talk) 08:49, 10 December 2015 (UTC)

Clarification asked for
The source does not say what products the reaction would yield. I think it would be PbO2 + 4HCl -> PbCl2 + Cl2 + 2H2O, but in any case it's not all that important for the story and won't be mentioned.--R8R (talk) 12:44, 13 February 2016 (UTC)

Para I don't yet know where to insert
Lead has been mined in Africa in the pre-colonial times, although exact dates are missing because there are no written sources of the mining, and there is only oral documentation and direct evidences of mining. Lead has been mined in the Congo basin(pp.130-131) and the Benue Trough(p.85). Peoples of eastern, south-eastern, and southern Africa are well known to exercise wire drawing.(p.105) In Kongo, people used lead for smelting—which proved to be a socially high activity—for both mechanical properties of the alloys and trading, as well as a currency.(pp.131-133) https://books.google.ru/books?id=oMgkHFiBTMEC&printsec=frontcover&dq=ancient+african+metallurgy&hl=en&sa=X&ved=0ahUKEwjm-cG6g_nKAhXk8XIKHZT8DV4Q6AEIJTAA#v=onepage&q=lead&f=false

Done--R8R (talk) 13:35, 15 February 2016 (UTC)