PENTANE* - (109-66-0)

Introduction

Name: pentane*; n-pentane; amyl hydride
* IUPAC
CAS Number: 109-66-0
Chemical Formula: C5H12 or CH3(CH2)3CH3
Molar Mass: 72.14878 g
State of Matter: colorless liquid
Mass Percent: C 83.235 %; H 16.764 % 
Isomers:  2,2-dimethylpropane*  •  2-methylbutane

Classification

• organic • alkane

Physical Properties

Melting Point:*
-129.7°C 1 = 143.45 K = -201.46°F
Boiling Point:*
36.2°C 2 = 309.35 K = 97.16°F
36.0°C 1 = 309.15 K = 96.8°F
36°C 3 = 309.15 K = 96.8°F
Density (g/cm3):
0.6262 at 20°C 1
* - 1 atm pressure

Solubility

Qualitative:
insoluble:  3
soluble:  3
miscible:  • 3

Bonding

Double Bonds: 0
Triple Bonds: 0
Sigma Bonds: 16
Pi Bonds: 0
Total: 16
Carboxyl Groups: 0
Hydroxyl Groups: 0
Hybridization: all carbons are sp3
Bonding: polar covalent
Ionic Character: 10.61 %

Thermochemistry

ΔHf° (g): -35.00 kcal/mol 4 = -146.44 kJ/mol
ΔHf° (ℓ): -41.47 kcal/mol = -173.5 kJ/mol 5
ΔHf° (ℓ): -41.36 kcal/mol 6 = -173.05 kJ/mol
ΔHf° (g): -35.00 kcal/mol 6 = -146.44 kJ/mol
S° (g): 83.40 cal/(mol•K) 7 = 348.95 J/(mol•K)
S° (ℓ): 62.79 cal/(mol•K) 9 = 262.71 J/(mol•K)
S° (g): 83.27 cal/(mol•K) 9 = 348.40 J/(mol•K)
ΔGf° (g): -2.00 kcal/mol 10 = -8.37 kJ/mol
ΔGf° (ℓ): -2.21 kcal/mol 12 = -9.25 kJ/mol
ΔGf° (g): -1.96 kcal/mol 12 = -8.20 kJ/mol
The heat of combustion is the amount of heat released when one mole of a substance undergoes combustion according to the general reaction equation:
CxHyOz + 0.25(4x+y-2z) O2 (g) → x CO2 (g) + 0.5y H2O (ℓ)

ΔHcomb° (g): -845.14 kcal = -3536.09 kJ
ΔHcomb° (ℓ): -838.672504780115 kcal = -3509.03 kJ
ΔHcomb° (ℓ): -838.78 kcal = -3509.47976 kJ
ΔHcomb° (g): -845.14 kcal = -3536.09 kJ

Safety Information

NFPA 704 Ratings:
Health: 1 - Exposure would cause irritation with only minor residual injury.
Flammability: 4 - Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Includes pyrophoric substances. Flash point below 23°C (73°F).
Reactivity: 0 - Normally stable, even under fire exposure conditions, and is not reactive with water.

For More Information

Sources

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 3-239.
(2) - Estok, George K. Organic Chemistry: A Short Text; W.B. Saunders: Philadelphia, 1959; p 29.
(3) - Shriner, Ralph L., Fuson, Reynold C., and Curtin, David Y. The Systematic Identification of Organic Compounds, 4th ed.; John Wiley & Sons: New York, 1962; p 314.
(4) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:87.
(5) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 5-42.
(6) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 9:69.
(7) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:87.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 5-42.
(9) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 9:69.
(10) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:87.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 5-42.
(12) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 9:69.