Paraffins
Definition and meaning of Paraffins in chemistry.
Paraffins are saturated hydrocarbons built entirely from carbon and hydrogen atoms. These atoms link together using only single chemical bonds. The general formula for an open chain paraffin is CnH2n+2.
In more detail
Most paraffins come directly from raw petroleum found deep underground. Refineries heat this crude oil to separate it into different groups. This sorting process happens based on the boiling point of each chemical.
These carbon chains are very stable and rarely react with other substances. This stability happens because their single bonds hold the atoms very tightly. The old Latin name actually means little affinity for this exact reason.
Paraffins also repel water very strongly due to their nonpolar nature. This lack of electric charge makes them perfect for waterproofing items. A common student mistake is thinking paraffin only means candle wax.
In reality, the length of the carbon chain completely changes the physical state. Short chains with one to four carbons create light gases at room temperature. Medium chains with five to seventeen carbons form liquid oils and fuels.
Only the very long carbon chains turn into the familiar solid waxes. You will find these chemicals acting as lubricants inside car engines. They also form the protective insulation wrapped around electrical wires.
Key facts
| General formula | CnH2n+2 for acyclic chains |
|---|---|
| Field | Organic Chemistry |
| Primary source | Crude oil and natural gas |
| Key property | Highly stable and water repelling |
| Bond type | Single carbon to carbon bonds only |
| Common forms | Gases, liquid oils, and solid waxes |
Octane is a famous liquid paraffin with eight carbon atoms (C8H18). It acts as a major energy source inside everyday liquid gasoline. Hexane (C6H14) is another shorter paraffin that chemists use in the lab. Scientists use hexane to pull oils out of plant seeds safely. Methane (CH4) is the simplest paraffin and burns as natural gas.
Frequently asked questions
Why are paraffins called 'parum affinis'?
The name comes from an old Latin phrase meaning little affinity. This refers to their extremely low reactivity due to strong single bonds.
How do paraffins differ from alkenes?
Paraffins contain only single chemical bonds between their carbon atoms. Alkenes contain at least one double bond, which makes them much more reactive.
Why do paraffins completely fail to mix with water?
Paraffins are nonpolar molecules with no electric charge to grab onto water molecules. The water molecules stick to each other and push the paraffin away.