Introduction
Group: 11 or I B
Atomic Weight: 107.8682
Period: 5
CAS Number: 7440-22-4
Classification
No Stable Isotopes
Solid
Liquid
Gas
Solid (Predicted)
Description • Uses/Function
Silver has been known since ancient times. It is mentioned in Genesis. Slag dumps in Asia Minor and on islands in the Aegean Sea indicate thatman learned to separate silver from lead as early as 3000 B.C. Silver occurs native and in ores such as argentite (Ag2S) and horn silver (AgCl); lead,lead-zinc, copper, gold, and copper-nickel ores are principal sources. Mexico, Canada, Peru, and the U.S. are the principal silver producers in thewestern hemisphere. Silver is also recovered during electrolytic refining of copper. Commercial fine silver contains at least 99.9% silver. Purities of99.999+% are available commercially. Pure silver has a brilliant white metallic luster. It is a little harder than gold and is very ductile and malleable,being exceeded only by gold and perhaps palladium. Pure silver has the highest electrical and thermal conductivity of all metals, and possesses thelowest contact resistance. It is stable in pure air and water, but tarnishes when exposed to ozone, hydrogen sulfide, or air containing sulfur. The alloysof silver are important. Sterling silver is used for jewelry, silverware, etc. where appearance is paramount. This alloy contains 92.5% silver, theremainder being copper or some other metal. Silver is of utmost importance in photography, about 30% of the U.S. industrial consumption going intothis application. It is used for dental alloys. Silver is used in making solder and brazing alloys, electrical contacts, and high capacity silver-zinc andsilver-cadmium batteries. Silver paints are used for making printed circuits. It is used in mirror production and may be deposited on glass or metalsby chemical deposition, electrodeposition, or by evaporation. When freshly deposited, it is the best reflector of visible light known, but is rapidlytarnishes and loses much of its reflectance. It is a poor reflector of ultraviolet. Silver fulminate (Ag2C2N2O2), a powerful explosive, is sometimes formedduring the silvering process. Silver iodide is used in seeding clouds to produce rain. Silver chloride has interesting optical properties as it can be madetransparent; it also is a cement for glass. Silver nitrate, or lunar caustic, the most important silver compound, is used extensively in photography. Whilesilver itself is not considered to be toxic, most of its salts are poisonous. Natural silver contains two stable isotopes. Forty nine other radioactive isotopesand isomers are known. Silver compounds can be absorbed in the circulatory system and reduced silver deposited in the various tissues of the body.A condition, known as argyria, results, with a greyish pigmentation of the skin and mucous membranes. Silver has germicidal effects and kills manylower organisms effectively without harm to higher animals. Silver for centuries has been used traditionally for coinage by many countries of the world.In recent times, however, consumption of silver has at times greatly exceeded the output. In 1939, the price of silver was fixed by the U.S. Treasuryat 71¢/troy oz., and at 90.5¢/troy oz. in 1946. In November 1961 the U.S. Treasury suspended sales of nonmonetized silver, and the price stabilizedfor a time at about $1.29, the melt-down value of silver U.S. coins. The Coinage Act of 1965 authorized a change in the metallic composition of thethree U.S. subsidiary denominations to clad or composite type coins. This was the first change in U.S. coinage since the monetary system wasestablished in 1792. Clad dimes and quarters are made of an outer layer of 75% Cu and 25% Ni bonded to a central core of pure Cu. The compositionof the one- and five-cent pieces remains unchanged. One-cent coins are 95% Cu and 5% Zn. Five-cent coins are 75% Cu and 25% Ni. Old silver dollarsare 90% Ag and 10% Cu. Earlier subsidiary coins of 90% Ag and 10% Cu officially were to circulate alongside the clad coins; however, in practicethey have largely disappeared (Gresham’s Law), as the value of the silver is now greater than their exchange value. Silver coins of other countries havelargely been replaced with coins made of other metals. On June 24, 1968, the U.S. Government ceased to redeem U.S. Silver Certificates with silver.Since that time, the price of silver has fluctuated widely. As of January 1996, the price of silver was about $5.30/troy oz. (17¢/g); however the pricehas fluctuated considerably due to market instability. 1
• "...gold and silver have been used as free metals since prehistoric times." 2
Physical Properties
Melting Point:3* 961.78 °C = 1234.93 K = 1763.204 °F
Electron Configuration: *[Kr] 5s1 4d10
n = 4
Electronegativity (Pauling scale):5 1.93
Specific Heat: 0.235 J/g°C 9 = 25.349 J/mol°C = 0.056 cal/g°C = 6.059 cal/mol°C
2 Ag (s) + 1 Cu(NO3)2 (aq) → 2 AgNO3 (aq) + Cu (s)
Earth - Source Compounds: sulfides 17
External Links:
Magazines:
(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:29.
Boiling Point:3* 2162 °C = 2435.15 K = 3923.6 °F
Sublimation Point:3
Triple Point:3
Critical Point:3
Density:4 10.5 g/cm3
* - at 1 atm
Electron Configuration
Block: d
Highest Occupied Energy Level: 5
Valence Electrons:
Quantum Numbers:
ℓ = 2
mℓ = 2
ms = -½
Bonding
Electropositivity (Pauling scale): 2.07
Electron Affinity:6 1.302 eV
Oxidation States: +1
Work Function:7 4.64 eV = 7.43328E-19 J
Ionization Potential
eV 8
kJ/mol
1
7.5762
731.0
Ionization Potential
eV 8
kJ/mol
2
21.49
2073.5
Ionization Potential
eV 8
kJ/mol
3
34.83
3360.6
Thermochemistry
Thermal Conductivity: 429 (W/m)/K, 27°C 10
Heat of Fusion: 11.3 kJ/mol 11 = 104.8 J/g
Heat of Vaporization: 250.58 kJ/mol 12 = 2323.0 J/g
State of Matter
Enthalpy of Formation (ΔHf°)13
Entropy (S°)13
Gibbs Free Energy (ΔGf°)13
(kcal/mol)
(kJ/mol)
(cal/K)
(J/K)
(kcal/mol)
(kJ/mol)
(s)
0
0
10.17
42.55128
0
0
(g)
68.01
284.55384
41.321
172.887064
58.72
245.68448
(s)
0.0
0
42.6
178.2384
(g)
284.9
1192.0216
173.0
723.832
246.0
1029.264
Isotopes
Nuclide
Mass 14
Half-Life 14
Nuclear Spin 14
Binding Energy
100Ag
99.91610(8)
2.01(9) min
(5)+
848.61 MeV
101Ag
100.91280(11)
11.1(3) min
9/2+
862.27 MeV
102Ag
101.91169(3)
12.9(3) min
5+
870.34 MeV
103Ag
102.908973(18)
65.7(7) min
7/2+
887.72 MeV
104Ag
103.908629(6)
69.2(10) min
5+
895.79 MeV
105Ag
104.906529(12)
41.29(7) d
1/2-
903.87 MeV
106Ag
105.906669(5)
23.96(4) min
1+
911.94 MeV
107Ag
106.905097(5)
STABLE
1/2-
920.01 MeV
108Ag
107.905956(5)
2.37(1) min
1+
928.08 MeV
109Ag
108.904752(3)
STABLE
1/2-
936.15 MeV
110Ag
109.906107(3)
24.6(2) s
1+
944.22 MeV
111Ag
110.905291(3)
7.45(1) d
1/2-
952.29 MeV
112Ag
111.907005(18)
3.130(9) h
2(-)
960.37 MeV
113Ag
112.906567(18)
5.37(5) h
1/2-
968.44 MeV
114Ag
113.908804(27)
4.6(1) s
1+
976.51 MeV
115Ag
114.90876(4)
20.0(5) min
1/2-
984.58 MeV
116Ag
115.91136(5)
2.68(10) min
(2)-
983.34 MeV
117Ag
116.91168(5)
73.6(14) s [72.8(+20-7) s]
1/2-#
991.41 MeV
118Ag
117.91458(7)
3.76(15) s
1-
999.48 MeV
119Ag
118.91567(10)
6.0(5) s
1/2-#
1,007.55 MeV
120Ag
119.91879(8)
1.23(4) s
3(+#)
1,015.62 MeV
121Ag
120.91985(16)
0.79(2) s
(7/2+)#
1,023.69 MeV
122Ag
121.92353(22)#
0.529(13) s
(3+)
1,022.45 MeV
123Ag
122.92490(22)#
0.300(5) s
(7/2+)
1,030.52 MeV
124Ag
123.92864(21)#
172(5) ms
3+#
1,038.59 MeV
125Ag
124.93043(32)#
166(7) ms
(7/2+)#
1,037.35 MeV
126Ag
125.93450(32)#
107(12) ms
3+#
1,045.42 MeV
127Ag
126.93677(32)#
79(3) ms
7/2+#
1,053.49 MeV
128Ag
127.94117(32)#
58(5) ms
1,052.25 MeV
129Ag
128.94369(43)#
44(7) ms [46(+5-9) ms]
7/2+#
1,060.32 MeV
130Ag
129.95045(36)#
~50 ms
0+
1,059.07 MeV
93Ag
92.94978(64)#
5# ms [>1.5 μs]
9/2+#
761.37 MeV
94Ag
93.94278(54)#
37(18) ms [26(+26-9) ms]
0+#
775.96 MeV
95Ag
94.93548(43)#
1.74(13) s
(9/2+)
790.55 MeV
96Ag
95.93068(43)#
4.45(4) s
(8+)
803.28 MeV
97Ag
96.92397(35)
25.3(3) s
(9/2+)
817.87 MeV
98Ag
97.92157(7)
47.5(3) s
(5+)
827.81 MeV
99Ag
98.91760(16)
124(3) s
(9/2)+
839.60 MeV
Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses. 14
Reactions
2 Ag (s) + 1 Pb(NO3)2 (aq) → 2 AgNO3 (aq) + Pb (s)
Cd (s gamma) + 2 AgNO3 (aq) → Cd(NO3)2 (aq) + 2 Ag (s) 15
Cu (s) + 2 AgNO3 (aq) → Cu(NO3)2 (aq) + 2 Ag (s)
Cu (s) + 2 AgNO3 (aq) → 2 Ag (s) + Cu(NO3)2 (aq) 16
Mg (s) + 2 AgNO3 (aq) → Mg(NO3)2 (aq) + 2 Ag (s)
Pb (s) + 2 AgNO3 (aq) → Pb(NO3)2 (aq) + 2 Ag (s)
Mn (s alpha) + 2 AgNO3 (aq) → Mn(NO3)2 (aq) + 2 Ag (s)
Abundance
Earth - Seawater: 0.00004 mg/L 18
Earth -
Crust:
0.075 mg/kg = 0.0000075% 18
Earth -
Total:
44 ppb 19
Mercury -
Total:
7.2 ppb 19
Venus -
Total:
49 ppb 19
Chondrites - Total: ~0.09 (relative to 106 atoms of Si) 20
Compounds
silver acetylide
silver azide
silver bromate
silver bromide
silver carbonate
silver chlorate
silver chloride
silver chromate
silver cyanide
silver dibromide
silver dichloride
silver dichromate
silver fluoride
Prices
Safety Information
Material Safety Data Sheet - ACI Alloys, Inc.
For More Information
American Elements
Chemical & Engineering News
Chemical Elements
ChemGlobe
Chemicool
Environmental Chemistry
(1) Moyer, Michael. How Much is Left?. Scientific American, September 2010, pp 74-81.
Sources
(2) - Whitten, Kenneth W., Davis, Raymond E., and Peck, M. Larry. General Chemistry 6th ed.; Saunders College Publishing: Orlando, FL, 2000; p 905.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(4) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(5) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(6) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 10:147-10:148.
(7) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(12) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(13) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 5:5.
(14) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(15) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 97.
(16) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 75.
(17) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(18) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(19) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(20) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.