Ethane, a colorless, odorless gas, can be broken down by a chemical change. It is the second-simplest hydrocarbon after methane, defined chemically as an alkane with the formula C2H6. A chemical change transforms the starting material into entirely new substances with different compositions and properties. Ethane is routinely subjected to these changes to release stored energy or convert it into valuable industrial materials.
Why Ethane Resists Change
Ethane is known for its high chemical stability, which is typical of its family, the alkanes. It is classified as a saturated hydrocarbon, meaning all the bonds between its atoms are single bonds. It contains one carbon-carbon (C-C) single bond and six carbon-hydrogen (C-H) single bonds.
These single bonds are particularly strong, requiring a substantial input of energy to break. This inherent strength explains why ethane is generally non-reactive under normal conditions, resisting interaction with most common chemicals. Breaking these strong covalent bonds is necessary for the chemical decomposition of ethane, differentiating it from a simple physical change.
Breaking Down Ethane Through Oxidation
The most common chemical change used to break down ethane is combustion, a rapid form of oxidation. When ethane is mixed with sufficient oxygen and ignited, the reaction is highly exothermic, releasing a large amount of energy as heat and light. This makes it a common fuel source.
In this complete oxidation, the ethane molecule is entirely broken apart, and its atoms are rearranged to form new compounds. The primary products are carbon dioxide (CO2) and water (H2O). This transformation into two completely different, non-combustible gases clearly demonstrates a chemical change used to generate power.
Breaking Down Ethane Through Heat and Catalysts
Ethane is also broken down industrially through steam cracking, a method that uses intense heat and sometimes catalysts to force a chemical transformation. This process is performed at extremely high temperatures, often with the addition of steam. Unlike combustion, this reaction is performed in the absence of oxygen to prevent complete burning of the hydrocarbon.
The immense thermal energy causes the strong C-C and C-H bonds to break, a process called homolytic cleavage, which forms highly reactive intermediate molecules called free radicals. The main goal of this cracking process is to convert it into smaller, more valuable hydrocarbons, rather than destroying the molecule completely.
The primary product of ethane cracking is ethylene (C2H4), an unsaturated hydrocarbon containing a carbon-carbon double bond. Ethylene is the most commonly manufactured petrochemical, serving as the raw material for nearly all plastics and various other chemicals. This industrial application transforms the stable ethane molecule into the foundational building blocks of the petrochemical industry.