Silver

Silver (Ag)

Introduction

Silver is a chemical element with the atomic number 47 in the periodic table. It constitutes 0.05 part per million of Earth’s crust and ranks as the 68th most abundant chemical element. The properties of this noble metal have been known even to the ancient civilizations. 

 

As a member of the transition metals family of elements, this relatively rare precious metal with a high economic value has one valence electron which makes element 47 a chemically inert substance. 

 

Silver’s most popular use is for making jewelry and silverware. It also has an important application in medicine, as well as in the electrical, electronic, and photographic industries. 

Fact Box

Chemical and Physical Properties of Silver

The symbol in the periodic table of elements: Ag

Atomic number: 47

Atomic weight (mass): 107.87 g.mol-1

Group number: 11

Period: 5 (d-block)

Color: Lustrous white-gray metal

Physical state: Solid at room temperature

Half-life: From less than 5 milliseconds [>1.5 µs] to 418(21) years

Electronegativity according to Pauling: 1.9

Density: 10.5 g.cm-3 at 20°C

Melting point: 961.78°C, 1763.2°F, 1234.93 K

Boiling point: 2162°C, 3924°F, 2435 K

Van der Waals radius: 0.144 nm

Ionic radius: 0.126 nm

Isotopes: 40

Most characteristic isotope: 107Ag

Electronic shell: [Kr] 4d105s1

The energy of the first ionization: 758 kJ.mol-1

The energy of the second ionization: 2061 kJ.mol-1

Discovery date: The ancient times

 

With the periodic table symbol Ag, atomic number 47, atomic mass of 107.87 g.mol-1, and electron configuration [Kr] 4d105s1, silver is a soft, very ductile, malleable, and lustrous white-gray metal. It reaches its boiling point at 2162°C, 3924°F, 2435 K, while the melting point is achieved at 961.78°C, 1763.2°F, 1234.93 K. 

 

This member of the transition metals family of elements has an electronegativity of 1.9 according to Pauling, whereas the atomic radius according to van der Waals is 0.144 nm.

 

Located between copper (Period 4) and gold (Period 6), silver is classified in the Period 5 of the periodic table and shares many chemical properties with its neighboring elements. Together with gold, platinum, iridium, osmium, ruthenium, and palladium, silver also belongs to the group of noble metals. 

 

Silver metal is characterized by excellent thermal and electrical conductivity, as well as strong anti-corrosive properties. It tarnishes only when exposed to hydrogen sulfide and ozone.                    

How Was Silver Discovered?

Silver is one of the first metals whose chemical and physical properties were utilized by ancient civilizations. In fact, silver, gold, copper, lead, and iron are the first five metals discovered by ancient civilizations. Throughout history, this noble metal has been used as a remedy for a wide array of medical conditions. Even Hippocrates (460 BC – 370 BC), the father of modern medicine, has observed the beneficial properties of silver

 

According to this Greek physician, silver could heal wounds and prevent various infections and diseases. It’s especially fascinating that the antimicrobial and antimicrobial properties of silver have been used prior to the discovery of antibiotics with almost equal purpose. 

 

Throughout the millennials and different civilizations, silver was almost always second to gold in both value and rank. In Greek mythology, the first and brightest age of man was called the Golden Age. The most prosperous time in the history of the world and humanity was followed by less and less prosperous times: the Silver Age, Bronze Age, and the final technological and cultural stage in the Stone Era – the Iron Age

How Did Silver Get Its Name?

The name of element 47 is derived from the Anglo-Saxon word for silver, ‘seolfor’. In turn, this Anglo-Saxon word stems from the ancient Germanic term ‘silabar’. In the periodic table, silver is classified under the symbol Ag. This abbreviation comes from the Latin word ‘argentum’, i.e. ‘shining, white’, and refers to the physical appearance of silver. 

Where Can You Find Silver?

Silver is the 65th most abundant chemical element traced in the Universe, while in the layers of our planet it occurs as the 68th most plentiful substance.

 

Humans have been mining silver for many millennials. The first evidence for exploitation of the natural silver resources date from around 3,000 BCE in Anatolia, now located in modern-day Turkey. Silver metal is often found together with lead in the mineral galena (mainly composed of lead sulfide).

 

In nature, silver mainly occurs as a compound in the copper, copper-nickel, lead, and lead-zinc ores. Element 47 typically occurs in four forms:

 

  • Pure;
  • Mineral;
  • Alloy;
  • Trace metal.

 

Depending on the geography, silver can be also traced along with gold, or mixed with quartz and ruby crystal formations. Nuggets of native silver are not such a rare sight in the river beds that run through a silver-rich location. 

 

The richest silver mines in the United States are found in Comstock Lode mines, Nevada, which is popularly labeled as “The Silver State”. Worldwide, Mexico, Peru, and China are ranked as the top producing countries of silver. 

List of Silver Minerals

The exhaustive list of silver-rich minerals includes the following items:


  • Acanthite
  • Aguilarite
  • Allargentum
  • Andorite
  • Aramayoite
  • Arcubisite
  • Argentite
  • Argentopyrite
  • Argyrodite
  • Arquerite
  • Aurorite
  • Berryite
  • Boleite
  • Bromargyrite
  • Canfieldite
  • Chlorargyrite
  • Chrisstanleyite
  • Crookesite
  • Dyscrasite
  • Empressite
  • Fettelite
  • Freibergite
  • Freieslebenite
  • Gabrielite
  • Hessite
  • Iodargyrite
  • Jalpaite
  • Krennerite
  • Marrite
  • Miargyrite
  • Pearceite
  • Petzite
  • Polybasite
  • Proustite
  • Pyrargyrite
  • Quetzalcoatlite
  • Samsonite (mineral)
  • Stephanite
  • Stromeyerite
  • Stützite
  • Sylvanite
  • Uytenbogaardtite
  • Xanthoconite


Silver in Everyday Life

Highly valued for its chemical properties and decorativeness, silver is commonly found in our everyday life. The wide array of its applications includes the following uses of element 47:

 

  • Silver sulfadiazine is a compound of element 47 that has a medical application as a strong antibacterial and antifungal agent. It usually comes in a form of topical cream that is used in the treatment of skin infections that occur in areas affected by burns. 
  • Water tanks on ships and airplanes are usually lined with a thin layer of silver that keeps the water fresh for a long time. Namely, silver water purification filters are utilized by many national and international airlines to prevent the growth of algae and bacteria in drinking water;
  • Silver electrical contacts are used in the manufacturing of keyboards;
  • As an antiseptic agent, a solution of silver nitrate is applied as eye drops for the newborn babies as gonorrhea or chlamydia prevention;
  • Batteries and mirrors also contain silver as one of the main components in their process of production;
  • Some first aid bandages contain silver ions. Silver antimicrobial bandages prevent the growth of a broad spectrum of microbes that may trigger an infection of the covered wound;
  • In dentistry, silver is used for dental fillings. Also, silver carbonate is one of the components in the cavities prevention treatments;
  • The anticorrosive properties of the silver metal are also utilized in the manufacturing of endotracheal tubes, blood and urinary catheter designs, orthopedic devices, vascular prostheses, and the sewing ring of prosthetic heart valves. 

Silver and Health

Before the invention of antibiotics, silver was the main antimicrobial and antiseptic agent used in medicine. The bactericidal activity of pure silver was commonly used in the treatment of skin burns to prevent wound infection, as well as to promote healing. Even after the introduction of antibiotics, topical silver is still used today as a powerful antimicrobial and antiseptic agent in post-operative incision dressings. 

Silver Supplements

Colloidal silver is a liquid substance containing elemental silver that is sometimes used as an alternative therapy for various skin conditions and infections. It has been in use among people even before modern antibiotics were developed. 

 

However, according to the U.S. Food and Drug Administration (FDA) study from 1999, this supplement does not comply with their regulations and standards. For this reason, colloidal silver is not approved as a supplement by the FDA since it’s not considered necessary or safe enough to be taken orally. 

 

Also, its inadequate use may lead to serious side effects and severe health conditions, such as hemorrhage, argyria (blue-grey discoloration of skin, nails, and mucous membranes), pulmonary edema (fluid on the lungs caused by congestive heart failure), bone marrow suppression (lowered immunity), Hepatorenal syndrome (a life-threatening medical condition that consists of rapid deterioration in kidney function), etc.

 

Important: Please note that this colloidal silver fact sheet is for educational and informative purposes only. We strongly advise that you seek medical advice from a qualified healthcare provider or trained health professionals before treating any medical problems with colloidal silver supplements.

How Dangerous Is Silver?

While pure elemental silver is considered a non-toxic substance and has many beneficial properties health-wise, its compounds are highly toxic and may pose a serious health hazard.  Some silver salts may even be carcinogenic. 

 

In addition, there are silver compounds that may pose a fire and explosion hazard, such as silver fulminate. This explosive compound is exceptionally sensitive to pressure and heat.

Silver Toxicity

Silver ions and silver compounds have a highly toxic effect on some bacteria, viruses, algae, and fungi that is similar to the toxicity of lead or mercury. Long-term exposure to silver metal may occur through inhalation, ingestion, or skin contact. The group of people at highest risk of overexposure to this chemical element includes the miners, individuals who implement silver-based supplements in their therapy, or metal industry workers. 

What Are the Symptoms of Silver Toxicity?

Inhalation of the soluble salts of silver can be lethal upon ingestion. The signaling symptoms of the toxicity of these silver compounds include:


  • Staggering,
  • Drowsiness;
  • Respiratory problems;
  • Headache;
  • Breathing difficulty;
  • Confusion;
  • Liver and lung damage;
  • Eye and kidney damage;
  • Anemia;
  • Cardiovascular problems;
  • Central nervous system damage.

 

If the aforementioned symptoms are not treated in a timely manner, they may lead to more serious health conditions such as argyria, or even coma and death. 

What is Argyria?

Prolonged exposure increases the absorbed levels of silver in our body, which causes damage to our body. When a large quantity of silver enters our body via different routes of exposure, it comes into contact with the acids in our stomach. This causes silver to corrode and transforms the metal into a toxic salt which triggers further damage to tissues and organs. 

 

When the individual with an abnormal accumulation of silver in their organism is exposed to sunlight, the chemical reaction triggered by sun rays colors the skin blue. Discoloration, also labeled as argyria, may also affect the whites of the eyes, as well as the internal organs. 

 

These symptoms of argyria typically occur in the mouth at first by coloring the gums and the tongue blue and are irreversible. Since argyria is quite a rare disease, its mild forms are often mistaken for cyanosis.

Environmental Effects of Silver

In its pure, elemental form, silver is generally not harmful to the environment. However, it can be released via various industrial processes and thus contaminate the geological, biological, and aquatic systems. On the other hand, the mining of silver often leads to land erosion which can greatly impact our environment in a negative way by polluting its systems. 

Isotopes of Silver

There are 40 isotopes of silver with atomic weight ranging from 93Ag to 132Ag. Naturally occurring silver (47Ag) is made up of two stable isotopes – 107Ag and 109Ag. Both of these silver forms occur in almost equal abundance in Earth’s crust. 

 

The primary decay mode of the forms of element 47 that come before the most abundant stable isotope (107Ag) is electron capture which results in palladium isotopes, while the primary mode of the isotopes after 108Ag is beta decay and produces cadmium isotopes.

 

Nuclide

[n 1]

Z N Isotopic mass (Da)

[n 2][n 3]

Half-life

[n 4]

Decay

mode

[n 5]

Daughter

isotope

[n 6][n 7]

Spin and

parity

[n 8][n 4]

Natural abundance (mole fraction)
Excitation energy[n 4] Normal proportion Range of variation
93Ag 47 46 92.94978(64)# 5# ms

[>1.5 µs]

β+ 93Pd 9/2+#
p 92Pd
94Ag 47 47 93.94278(54)# 37(18) ms

[26(+26−9) ms]

β+ 94Pd 0+#
95Ag 47 48 94.93548(43)# 1.74(13) s β+ (>99.9%) 95Pd (9/2+)
β+, p (<.1%) 94Rh
96Ag 47 49 95.93068(43)# 4.45(4) s β+ (96.3%) 96Pd (8+)
β+, p (3.7%) 95Rh
97Ag 47 50 96.92397(35) 25.3(3) s β+ 97Pd (9/2+)
98Ag 47 51 97.92157(7) 47.5(3) s β+ (99.99%) 98Pd (5+)
β+, p (.0012%) 97Rh
99Ag 47 52 98.91760(16) 124(3) s β+ 99Pd (9/2)+
100Ag 47 53 99.91610(8) 2.01(9) min β+ 100Pd (5)+
101Ag 47 54 100.91280(11) 11.1(3) min β+ 101Pd 9/2+
102Ag 47 55 101.91169(3) 12.9(3) min β+ 102Pd 5+
103Ag 47 56 102.908973(18) 65.7(7) min β+ 103Pd 7/2+
104Ag 47 57 103.908629(6) 69.2(10) min β+ 104Pd 5+
105Ag 47 58 104.906529(12) 41.29(7) d β+ 105Pd 1/2−
106Ag 47 59 105.906669(5) 23.96(4) min β+ (99.5%) 106Pd 1+
β (0.5%) 106Cd
107Ag[n 9] 47 60 106.905097(5) Stable[n 10] 1/2− 0.51839(8)
108Ag 47 61 107.905956(5) 2.37(1) min β (97.15%) 108Cd 1+
β+ (2.85%) 108Pd
109Ag[n 11] 47 62 108.904752(3) Stable[n 10] 1/2− 0.48161(8)
110Ag 47 63 109.906107(3) 24.6(2) s β (99.7%) 110Cd 1+
EC (.3%) 110Pd
111Ag[n 11] 47 64 110.905291(3) 7.45(1) d β 111Cd 1/2−
112Ag 47 65 111.907005(18) 3.130(9) h β 112Cd 2(−)
113Ag 47 66 112.906567(18) 5.37(5) h β 113mCd 1/2−
114Ag 47 67 113.908804(27) 4.6(1) s β 114Cd 1+
115Ag 47 68 114.90876(4) 20.0(5) min β 115mCd 1/2−
116Ag 47 69 115.91136(5) 2.68(10) min β 116Cd (2)−
117Ag 47 70 116.91168(5) 73.6(14) s

[72.8(+20−7) s]

β 117mCd 1/2−#
118Ag 47 71 117.91458(7) 3.76(15) s β 118Cd 1-
119Ag 47 72 118.91567(10) 6.0(5) s β 119mCd 1/2−#
120Ag 47 73 119.91879(8) 1.23(4) s β (99.99%) 120Cd 3(+#)
β, n (.003%) 119Cd
121Ag 47 74 120.91985(16) 0.79(2) s β (99.92%) 121Cd (7/2+)#
β, n (.076%) 120Cd
122Ag 47 75 121.92353(22)# 0.529(13) s β (>99.9%) 122Cd (3+)
β, n (<.1%) 121Cd
123Ag 47 76 122.92490(22)# 0.300(5) s β (99.45%) 123Cd (7/2+)
β, n (.549%) 122Cd
124Ag 47 77 123.92864(21)# 172(5) ms β (99.9%) 124Cd 3+#
β, n (.1%) 123Cd
125Ag 47 78 124.93043(32)# 166(7) ms β (>99.9%) 125Cd (7/2+)#
β, n (<.1%) 124Cd
126Ag 47 79 125.93450(32)# 107(12) ms β (>99.9%) 126Cd 3+#
β, n (<.1%) 125Cd
127Ag 47 80 126.93677(32)# 79(3) ms β (>99.9%) 127Cd 7/2+#
β, n (<.1%) 126Cd
128Ag 47 81 127.94117(32)# 58(5) ms β 128Cd
129Ag 47 82 128.94369(43)# 44(7) ms

[46(+5−9) ms]

β (>99.9%) 129Cd 7/2+#
β, n (<.1%) 128Cd
130Ag 47 83 129.95045(36)# ~50 ms β 130Cd 0+
131Ag 47 84 35 ms β 131Cd
132Ag 47 85 28 ms β 132Cd

Source: Wikipedia

List of Silver Compounds 

Silver’s most common oxidation state in a chemical compound is +1. Despite being a chemically inactive element, silver reacts with sulfuric acid and nitric acid. When exposed to H2O, element 47 maintains a stable structure.  

 

The list of most commonly occurring and prepared silver compounds contains the following items:


  • AgInSbTe
  • Argyrol
  • Fulminating silver
  • Organosilver chemistry
  • Potassium argentocyanide
  • Rubidium silver iodide
  • Silver acetate
  • Silver acetylide
  • Silver arsenate
  • Silver azide
  • Silver behenate
  • Silver bromate
  • Silver bromide
  • Silver carbonate
  • Silver chlorate
  • Silver chloride
  • Silver chromate
  • Silver cyanate
  • Silver cyanide
  • Silver diamine fluoride
  • Silver dichromate
  • Silver diethyldithiocarbamate
  • Silver fulminate
  • Silver halide
  • Silver hexafluorophosphate
  • Silver iodate
  • Silver iodide
  • Silver molybdate
  • Silver nitrate
  • Silver nitride
  • Silver nitrite
  • Silver oxalate
  • Silver oxide
  • Silver perchlorate
  • Silver permanganate
  • Silver perrhenate
  • Silver phosphate
  • Silver proteinate
  • Silver selenite
  • Silver subfluoride
  • Silver sulfadiazine
  • Silver sulfate
  • Silver sulfide
  • Silver sulfite
  • Silver telluride
  • Silver tetrafluoroborate
  • Silver thiocyanate
  • Silver trifluoromethanesulfonate
  • Silver(I,III) oxide
  • Silver(I) fluoride
  • Silver(I) hyponitrite
  • Silver(I) selenide
  • Silver(II) fluoride
  • Silver(III) fluoride
  • Tetrakis(pyridine)silver(II) peroxydisulfate
  • Tollens’ reagent
  • Walden reductor
  • Zinag
  • Zinagizado


5 Interesting Facts and Explanations

 

  1. Silver of 92.5% purity is labeled as sterling silver. Also known as ‘925 sterling silver’, this metal alloy contains 92.5% silver (Ag) and 7.5% copper (Cu). It’s popularly used for making jewelry and other decorative objects. Most investors who deal in precious metals usually trade in sterling silver.
  2. After the Spanish conquest of the Americas in 1492, the mining of silver rapidly increased and overshadowed all other metals on the market. Comstock Lode mines in Nevada, United States is where the silver-mining frenzy began in the 15th century.
  3. Element 47 has the highest electrical conductivity of all metals classified in the periodic table. 
  4. At the beginning of the 20th century, people used to put silver coins in milk bottles to prolong the freshness and shelf-life of dairy products. 
  5. One fifth of the silver quantities produced in the world today is obtained via methods of recycling.