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{{infobox lead}}
{{wiktionary}}
[[File:Lead-2.jpg|thumb|Lead]]
'''Lead''' (pronounce: "/'lɛd/") is a [[chemical element]]. Its [[chemical symbol]] is '''Pb''', which comes from ''plumbum'', the [[Latin]] word for lead.<ref>{{Cite web | url = http://www.bbc.co.uk/history/ancient/romans/tech_04.shtml | publisher = BBC | title = Discovering Roman Technology | accessdate = 2009-10-03 | archive-date = 2009-02-16 | archive-url = https://web.archive.org/web/20090216165058/http://www.bbc.co.uk/history/ancient/romans/tech_04.shtml | url-status = dead }}</ref> Its [[atomic number]] is 82, [[atomic mass]] is 207.2 and has a melting point of 327.8°C. It is a very [[poison|poisonous]] and heavy [[metal]], and is also the ending element to the [[Stable element|stable]] elements, although the next element, bismuth, is so weakly radioactive that it can be considered stable for practical purposes.<ref>{{cite web |url=https://www.thebismuthsmith.com/is-bismuth-radioactive-setting-the-record-straight/ |title=Is Bismuth Radioactive? Setting the Record Straight |website=The Bismuth Smith |publisher=The Bismuth Smith Inc |accessdate=8 March 2024}}</ref>

==Properties==
===Physical properties===
[[File:Lead powder burning (5).JPG|thumb|Lead powder burning]]
Lead is a shiny, gray-blue [[poor metal]]. It gets [[tarnish]]ed easily to a dull gray color. It is soft and [[wikt:malleable|malleable]]. It is very shiny when it is melted. It is very heavy. It is very [[corrosion]]-resistant. It is made stronger by adding [[antimony]] or [[calcium]]. It can form an alloy with [[sodium]]. It is toxic to people and animals when swallowed.

===Chemical properties===
[[File:FlammenfärbungPb.png|50px|right|Flame test for lead]]
Lead burns in air with a grayish-white flame, making toxic fumes of [[lead(II) oxide]]. Only the surface is corroded by air. It dissolves in [[nitric acid]] to make [[lead(II) nitrate]]. It does not dissolve in [[sulfuric acid|sulfuric]] or [[hydrochloric acid]]. It reacts with [[sodium nitrate]] to make lead(II) oxide and [[sodium nitrite]]. It reacts with [[chlorine]] to make [[lead(II) chloride]]. Lead(II) oxide reacts with [[lead sulfide]] to make lead metal and [[sulfur dioxide]].

===Chemical compounds===
Lead makes [[chemical compound]]s in two main [[oxidation state]]s: +2 and +4. +2 compounds, also known as lead(II) compounds or plumbous compounds, are weak [[oxidizing agent]]s. +4 compounds, also known as lead(IV) compounds or plumbic compounds, are strong oxidizing agents. Lead compounds are toxic just like the element. The lead [[halide]]s do not dissolve in water. [[Lead(IV) oxide]] is the most common lead(IV) compound. It is a black solid. The lead oxides are all colored, while the other salts are white or colorless. [[Lead nitrate]] and [[lead(II) acetate]] are the [[solubility|soluble]] compounds of lead.

;+2 compounds
This state is more common than the +4 state. These are weak [[oxidizing agent]]s. All but the oxides are colorless or white.
*[[Lead(II) acetate]], colorless soluble
*[[Lead(II) arsenate]], insoluble former pesticide
*[[Lead(II) bromide]], insoluble
*[[Lead(II) carbonate]], white, used as pigment
*[[Lead(II) chloride]], insoluble
*[[Lead(II) nitrate]], soluble, colorless
*[[Lead(II) oxide]], red or yellow
*[[Lead(II) sulfate]], white, found in lead acid batteries
*[[Lead(II) sulfide]], black, common as mineral

;Mixed oxidation state compounds
Mixed oxidation state compounds contain lead in the +2 and +4 oxidation state.
*[[Lead(II,IV) oxide]], red, oxidizing agent

;+4 compounds
These are less common. They are strong [[oxidizing agent]]s. 
*[[Lead(IV) acetate]], oxidizing agent, colorless
*[[Lead(IV) oxide]], dark brown, oxidizing agent'''Cobalt compounds''' are [[chemical compound]]s containing [[cobalt]] [[ion]]s. 

<gallery>
File:Lead(II) chloride.jpg|Lead(II) chloride
File:Lead(II) nitrate 1.jpg|Lead(II) nitrate
File:Lead dioxide.jpg|Lead(IV) oxide
File:Red lead.jpg|Lead(II,IV) oxide
File:Lead monoxide.jpg|Lead(II) oxide
</gallery>

==Occurrence==
<gallery>
File:Lead-34330.jpg|Lead found in the ground
File:Galena.jpg|Galena
</gallery>
Lead is found very rarely in the earth's crust as a metal. Normally, lead is in the [[mineral]] [[galena]]. Galena is [[lead sulfide]]. Galena is the main lead ore.

==History==
Lead was used for thousands of years because it is easy to get from the ground and easy to shape and work with. The Romans used lead very commonly. They used it for pipes, drinking vessels, and [[fastener]]s.

==Preparation==
Lead is made from galena. Galena is made pure by [[froth flotation]] to get all the impurities out. Then the lead sulfide is roasted in a furnace to make [[lead(II) oxide]]. The lead(II) oxide is heated with [[Coke (fuel)|coke]] to make liquid lead metal.

==Uses==
===As an element===
[[Image:Lead shielding.jpg|thumb|The dark bricks are made of lead. They are meant to keep people safe from the radioactive material inside.]]
Lead is used in the [[ballast]] of [[sailboat]]s. It is also used in weight belts for [[scuba diving]]. It is also used to make [[shotgun]] pellets and [[bullet]]s for [[small arm]]s. Some [[printing press]]es use lead type because it can be easily shaped. It can be used outside because it does not corrode in water. 

Most lead is used in [[lead acid battery|lead acid batteries]], though. The lead is [[oxidation|oxidized]], making [[electricity]]. Sheets of lead are used to block sound in some places. Lead is used in radiation shielding. Molten lead can be used as a [[coolant]] in [[nuclear reactor]]s. It used to be mixed with [[tin]] to make the pipes in [[pipe organ]]s. Different amounts of lead make different sounds. In addition, lead has found its usage in [[solder]].

It is used in some solder. It is used in covering for wires that carry high voltage. Some [[tennis]] rackets have lead in them to make them heavier. It is used to balance wheels of cars, to make statues, and to make decorative looks in buildings.

===As chemical compounds===
Many lead compounds are used to make colored [[glaze]]s in [[ceramic]]s. Lead can be used in [[PVC]] pipes. Lead compounds are added to [[candle]]s to make them burn better. [[Lead glass]] has lead(II) oxide in it. Lead compounds are still used as [[pigment]]s in some places. Lead compounds were added to gasoline, but are now outlawed. Some lead compounds are [[semiconductor]]s and are used in [[photodetector]]s. 

===Old uses===
Lead was used in many red, yellow, and white pigments in paints. Lead was also used in [[pesticide]]s. Lead used to be used in pipes carrying water, but now it is not because lead can leach into the water.

==Safety==
Although it can be safely touched, exposure to lead should be avoided – it is very [[toxic]] to humans and other [[animal]]s when swallowed, and its use is restricted in many [[country|countries]]. 

If someone is exposed to lead for a long time, it ruins their [[kidney]]s and gives them [[abdomen|abdominal]] pains. Lead also ruins the [[nervous system]]. Lead paint was being eaten by children and they were getting [[lead poisoning]].

The best way to understand lead and its properties is to read its [[MSDS]].

==Related pages==
*[[List of common elements]]
*[[Lead poisoning]]

==References==
{{reflist}}

{{Periodic Table}}

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{{authority control}}
[[Category:Post-transition metals]]