The key difference between hexane and n-hexane is that hexane has branched structures, whereas n-hexane is an un-branched hexane structure.
Organic molecules are molecules that consist of carbons. Hydrocarbons are organic molecules that consist of only carbon and hydrogen atoms. Hydrocarbons can be aromatic or aliphatic. They are mainly divided into few types as alkanes, alkenes, alkynes, cycloalkanes and aromatic hydrocarbons. Hexane and n-hexane are alkanes, or otherwise, known as saturated hydrocarbons. They have the highest number of hydrogen atoms a molecule can accommodate. All the bonds between carbon atoms and hydrogens are single bonds. Hence, bond rotation is allowed between any atoms. They are the simplest type of hydrocarbons. Saturated hydrocarbons have the general formula of CnH2n+2. These conditions slightly differ for the cycloalkanes because they have cyclic structures.
CONTENTS
1. Overview and Key Difference
2. What is Hexane
3. What is n-Hexane
4. Side by Side Comparison – Hexane vs n-Hexane in Tabular Form
5. Summary
What is Hexane?
As stated above, a hydrocarbon is a saturated alkane. It has six carbon atoms; therefore, has the formula of C6H14. The molar mass of hexane is 86.18 g mol−1. Hexane is the common name used to indicate all molecules with this formula. There are a number of structural isomers we can draw to match this formula but, in IUPAC nomenclature, we use hexane specifically to indicate unbranched molecule, and it is also known as n-hexane. Other structural isomers are like methylated molecules of pentane and butane. They are known as isohexane and neohexane. They have the following structures.
From these hexane structures, 2-methylpentane, 3-methylpentane and 2,3-dimethylbutane are examples of isohexane, whereas 2,2-dimethylbutane is an example for a neohexane.
Hexane is mainly produced in the crude oil refining process. Hexane is extracted when the oil is boiling at 65–70 °C. Since hexane isomers have somewhat similar boiling points, they evaporate at the same temperature range. However, their melting points are different. Hexane is in the liquid form at the room temperature and has an odour like gasoline. It is a colourless liquid. Hexane dissolves slightly in water. At room temperature, it tends to evaporate slowly into the atmosphere. Hexane vapour can be explosive and hexane itself is highly flammable. Hexane is a non-polar solvent, and it is used as a solvent in the laboratory.
Not only pure hexane is used as solvents, but there are various kinds of solvents made using hexane. Other than that, hexane is used to make leather products, glues, for textile manufacturing, cleansing products, etc. Hexane is used to extract non-polar substances like oil and grease when analyzing water and soil.
What is n-Hexane?
n –Hexane or normal hexane is the un-branched structure of hexane with the molecular formula C6H14. The boiling point of n-hexane is 68.7 oC, while the melting point is −95.3 oC. n-hexane is used in the process of extracting oil from seeds such as safflower, soybean and cotton.
What is the Difference Between Hexane and n-Hexane?
Hexane is a mixture of the compounds with the formula C6H14. Hexane has branched structures, whereas n-hexane is an un-branched hexane structure. n-Hexane is a structural isomer of hexane. Moreover, n-Hexane has a higher boiling point compared to other hexanes. However, overall, their boiling points fall within a small temperature range. In addition, n-Hexane has a considerable vapour pressure at room temperature.
Summary – Hexane vs n-Hexane
n-Hexane is a structural isomer of hexane. The key difference between hexane and n-hexane is that hexane has branched structures, whereas n-hexane is an un-branched hexane structure.
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1. “CNX Chem 20 01 ex1 15 img” By OpenStax – (CC BY 4.0) via Commons Wikimedia