SILVER SULFIDE - (21548-73-2)

Introduction

Name: silver sulfide
* IUPAC
CAS Number: 21548-73-2
Chemical Formula: Ag2S
Molar Mass: 247.8014 g
Mass Percent: Ag 87.060 %; S 12.939 % 

Classification

• inorganic

Uses/Function

• "...is black and forms a dull film over the bright metal [silver]." 1

Bonding

Bonding: polar covalent
Ionic Character: 19.70 %

Thermochemistry

ΔHf° (s alpha orthorhombic): -7.79 kcal/mol 2 = -32.59 kJ/mol
ΔHf° (s beta): -7.03 kcal/mol 2 = -29.41 kJ/mol
S° (s alpha orthorhombic): 34.42 cal/(mol•K) 3 = 144.01 J/(mol•K)
S° (s beta): 36.0 cal/(mol•K) 3 = 150.62 J/(mol•K)
ΔGf° (s alpha orthorhombic): -9.72 kcal/mol 4 = -40.67 kJ/mol
ΔGf° (s beta): -9.43 kcal/mol 4 = -39.46 kJ/mol

For More Information

Sources

(1) - Brady, James E. and Senese, Fred. Chemistry: Matter and Changes, 4th ed.; John Wiley and Sons: Hoboken, New Jersey, 2004; p 1008.
(2) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(3) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(4) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.