View source for Group 11 element

{{Unreferenced|date=December 2009}}
{| style="float: right; border: 1px solid #ccc; margin: 0.5em 0pt 0.8em 1.4em; padding: 3px !important; width: 75px;"
! <small>[[Group (periodic table)|Group]]</small>&nbsp;→!! 11
|-
! ↓&nbsp;<small>[[Period (periodic table)|Period]]</small>
|- align=center
| [[Period 4 element|'''4''']]
| {{element cell| [[File:Cu-Scheibe.JPG|150px|Copper macro etched]]<br />29|Copper|Cu| |Solid|Transition metals|Primordial}}
|- align=center
| [[Period 5 element|'''5''']]
| {{element cell|[[File:Silver crystal.jpg|150px|Silver dendritic crystal]]<br />47|Silver |Ag| |Solid|Transition metals|Primordial}}
|- align=center
| [[Period 6 element|'''6''']]
| {{element cell|[[File:Gold-crystals.jpg|150px|Gold crystals]]<br />79|Gold|Au| |Solid|Transition metals|Primordial}}
|- align=center
| [[Period 7 element|'''7''']]
| {{element cell| 111|Roentgenium|Rg| |Solid|Transition metals|Synthetic}}
|-
| colspan="2"|
----
<center>Legend
{|
| colspan="2" style="text-align: center; border: 1px solid #AAAAAA; background:{{Element color/Transition metals}};"|<small>''Transition metal''</small>
|-
| colspan="2" style="text-align: center; border: {{element frame/Primordial}};" |<small>''[[Primordial element]]''</small>
|-
| colspan="2" style="text-align: center; border: {{element frame/Synthetic}};" |<small>''[[Synthetic elements|Synthetic]]''</small>
|}</center>
|}
A '''Group 11 element''' is one in the [[chemical series|series]] of [[Chemical element|elements]] in [[periodic table group|group 11]] ([[IUPAC]] style) in the [[periodic table]], consisting of [[transition metal]]s which are the traditional coinage metals of [[copper]] ('''Cu'''), [[silver]] ('''Ag'''), and [[gold]]  ('''Au'''). [[Roentgenium]] ('''Rg''') belongs to this group of elements based on its [[electron configuration|electronic configuration]], but it is a short-lived [[transactinide]] with a 22.8 seconds [[Half-life (element)|half-life]] that has only been observed in laboratory conditions. The name "'''coinage metals'''" is often used in casual speech to refer to these elements, but various cultures have used many other metals in coinage including [[aluminium]], [[lead]], [[nickel]], [[stainless steel]],  and [[zinc]].

==History==
All the elements of the group except Roentgenium have been known since prehistoric times, as all of them occur in metallic form in nature and no extraction metallurgy has to be used to produce them.

==Characteristics==
Like other groups, the members of this family show patterns in its [[electron configuration]], especially the outermost shells resulting in trends in chemical behavior:

{| class="wikitable" border="1" cellpadding="3" cellspacing="0"
|-
![[Atomic number|Z]] !! [[Chemical element|Element]] !! [[Electron shell|No. of electrons/shell]] 
|-
| 29 || copper || 2, 8, 18, 1
|- 
| 47 || silver || 2, 8, 18, 18, 1
|- 
| 79 || gold || 2, 8, 18, 32, 18, 1
|- 
| 111 || roentgenium || 2, 8, 18, 32, 32, 18, 1
|}

They are all relatively inert, [[corrosion]]-resistant [[metal]]s.  Copper and gold are colored.

These elements have low [[electrical resistivity]] so they are used for wiring. Copper is the cheapest and most widely used. [[Bond wire]]s for [[integrated circuit]]s are usually gold. Silver and silver plated copper wiring are found in some special applications.

==Applications==
These metals, especially silver, have unusual properties that make them essential for industrial applications outside of their monetary or decorative value. They are all excellent [[Conductor (material)|conductors]] of [[electricity]].   The most conductive of all metals are silver, copper and gold in that order.  Silver is also the most thermally conductive element, and the most light reflecting element. Silver also has the unusual property that the tarnish that forms on silver is still highly electrically conductive. 

Copper is used extensively in electrical wiring and circuitry. Gold contacts are sometimes found in precision equipment for their ability to remain corrosion-free. Silver is used widely in mission-critical applications as electrical contacts, and is also used in [[photography]] (because [[silver nitrate]] reverts to metal on exposure to light), [[agriculture]], [[medicine]], [[audiophile]] and scientific applications.

Gold, silver, and copper are quite soft metals and so are easily damaged in daily use as coins. Precious metal may also be easily abraded and worn away through use. In their [[numismatics|numismatic]] functions these metals must be [[alloy]]ed with other metals to afford coins greater durability. The alloying with other metals makes the resulting coins harder, less likely to become deformed and more resistant to wear.

'''Gold coins:'''  [[Gold coin]]s are typically produced as 90% gold (e.g. with pre-1933 US coins), or 22 [[carat (purity)|carat]] (92%) gold (e.g. current [[Coin collecting|collectible coins]] and [[Krugerrand]]s), with copper and silver making up the remaining weight in each case.  Bullion gold coins are being produced with up to 99.999% gold (in the [[Canadian Gold Maple Leaf]] series).

'''Silver coins:'''  [[Silver coin]]s are typically produced as either 90% silver - in the case of pre 1965 US minted coins (which were circulated in many countries), or [[sterling silver]] (92.5%) coins for pre-1920 British Commonwealth and other silver coinage, with copper making up the remaining weight in each case.

'''Copper coins:'''  Copper coins are often of quite high purity, around 97%, and are usually alloyed with small amounts of [[zinc]] and [[tin]].

[[Inflation]] has caused the [[face value]] of coins to fall below the [[hard currency]] value of the historically used metals.  This had led to most modern coins being made of [[base metals]] - [[Cupronickel|copper nickel]] (around 80:20, silver in color) is popular as are nickel-[[brass]] (copper (75), nickel (5) and zinc (20), gold in color), [[manganese]]-brass (copper, zinc, manganese, and nickel), [[bronze]], or simple plated [[steel]].

==References==
{{reflist}}
==Related pages==
{|style="width: 80%; text-align: center;" border="1" cellpadding="2" 
|style="vertical-align: top;" colspan="1" rowspan="3">|Explanation of right side periodic table slice:
|style="background-color:#ffc0c0"|[[Transition metal]]s
|| atomic numbers in <span style="color:black">black</span> are solids
|style="border:solid 1px black;padding:1px;"|solid borders are older than the [[Earth]] ([[Primordial element]]s)
|style="border:dashed 1px black;padding:1px;"|dashed borders have no isotopes older than the earth
|}

{{PeriodicTablesFooter}}

{{DEFAULTSORT:Group 11 Element}}
[[Category:Groups (periodic table)|11]]
[[Category:Currency]]
[[Category:Coins]]