Basic Information

Chinese Name: 正庚烷

English Name: n-Heptane

CAS No.: 142-82-5

Molecular Formula: C₇H₁₆

Molecular Weight: 100.21 g/mol

Structure: Straight-chain alkane (CH₃CH₂CH₂CH₂CH₂CH₂CH₃)

Appearance: Colorless, volatile liquid

Odor: Mild, gasoline-like odor

Boiling Point: 98.4 °C

Melting Point: −90.6 °C

Density (20 °C): 0.684 g/cm³

Flash Point: −4 °C (closed cup)

Vapor Pressure (20 °C): ~4.0 kPa

Solvent Properties

Solubility

Insoluble in water; miscible with ethanol, ether, chloroform, acetone, benzene and most other organic solvents.

Solvent Characteristics

Non-polar solvent (low dielectric constant) with good dissolving power for oils, fats, waxes and non-polar organic compounds. It has a moderate evaporation rate, slower than n-hexane, and low surface tension, suitable for dissolution and cleaning.

Main Applications

Reference standard for octane number (n-heptane has an octane number of 0, used to calibrate gasoline quality).

Organic synthesis solvent and reaction medium, suitable for non-polar reaction systems.

Industrial cleaning agent and degreaser, used to remove oil, grease and wax on metal parts and precision instruments.

Component in adhesives, paints, inks and coatings, used to adjust viscosity and improve leveling property.

Laboratory solvent for chromatography, extraction and sample preparation.

Component of gasoline and aviation fuel, used to adjust fuel volatility and octane number.

Safety

Hazard Class: Highly flammable liquid and vapor

Fire & Explosion: Vapors can form explosive mixtures with air (1.0%–6.0% by volume); there is a risk of backflash and combustion when exposed to ignition sources.

Health Hazards: Inhalation of vapor may cause drowsiness, dizziness and headache; prolonged exposure can irritate the respiratory tract. Skin contact may cause dryness and defatting; eye contact causes irritation; ingestion is harmful.

Handling & Storage: Keep away from heat, sparks and open flames; use explosion-proof equipment. Store in a cool, well-ventilated area, separated from oxidants and acids. Wear protective gloves, goggles and respiratory protection when necessary.