- Methylethyl methane
Contains isobutane and n-butane, which are chemically similar. An colorless gas with a faint disagreeable odor.
As producer gas, in manufacture of synthetic rubbers.
Registry Numbers and Inventories.
EC Index Number
Extremely flammable; Carcinogenic Category 1; Mutagenic Category 2
S 9 16 33
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
1556 (20 C)
Vapor density (air=1)
Odor Threshold Odor threshold 50,000 ppm
0.579 g/cm3 (20 C0
Solubility in water
61 mg/L (20 C)
0.0074 cp (20 C)
14.87 g/s2 (20 C)
1.3326 (20 C)
1.0 (25 C)
Partition coefficient, pKow
0.002/K at 20 C
Heat of fusion
Heat of vaporization
Heat of combustion
Hazards and Protection.
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Wear appropriate protective gloves, clothing and goggles. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids.
Self-contained breathing apparatus and safety goggles.
ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. If possible, turn leaking containers so that gas escapes rather than liquid. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Do not direct water at spill or source of leak. Prevent spreading of vapors through sewers, ventilation systems and confined areas. Isolate area until gas has dispersed. CAUTION: When in contact with refrigerated/cryogenic liquids, many materials become brittle and are likely to break without warning.
Incompatible with strong oxidizing agents such as nitric acid.
Upper exp. limit, %
Lower exp. limit, %
DO NOT EXTINGUISH A LEAKING GAS FIRE UNLESS LEAK CAN BE STOPPED. SMALL FIRES: Dry chemical or carbon dioxide. LARGE FIRES: Water spray or fog. Move containers from fire area if you can do it without risk. FIRE INVOLVING TANKS: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn.
Vapors from liquefied gas are initially heavier than air and spread along ground. Vapors may travel to source of ignition and flash back. Containers may explode when heated. Ruptured cylinders may rocket.
When heated, emits acrid fumes.
Rapid breathing and rapid heart rate are common. In severe cases abnormally low blood pressure, apnea, and cardiac arrest develop. Various disturbances including headache, dizziness, mood disturbances, numbness of the extremities, sleepiness, mental confusion, poor judgement and coordination, and memory loss may occur. Prolonged or severe hypoxia results in unconsciousness. Prolonged asphyxia may produce CNS injury. Hemiparesis has been reported with volatile substance abuse. Cerebral edema with brainstem herniation may occur. Seizures have been reported following intentional inhalation.
Nausea, vomiting, and gastrointestinal hemorrhage may develop.
Hyperventilation may develop.
Dermal exposure may cause frostbite injury. Severe tissue burns have been reported.
Decreases in night vision, visual acuity, and visual fields (tunnel vision) may occur. Frothy mucous may be seen.
This compound is a gas, therefore inhalation is the first route of exposure.
IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used.
CAUTION: Exposure of skin to compressed gases may result in freezing of the skin. Treatment for frostbite may be necessary. Remove the victim from the source of contamination. IMMEDIATELY wash affected areas gently with COLD water (and soap, if necessary) while removing and isolating all contaminated clothing. Dry carefully with clean, soft towels. If symptoms such as inflammation or irritation develop, IMMEDIATELY call a physician or go to a hospital for treatment.
First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. If symptoms (such as redness or irritation) develop, immediately transport the victim to a hospital.