Hexane (/ˈhɛkseɪn/) or n-hexane is an organic compound, a straight-chain alkane with six carbon atoms and the molecular formula C6H14.[7] Hexane is a colorless liquid, odorless when pure, and with a boiling point of approximately 69 °C (156 °F). It is widely used as a cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvent, and modern gasoline blends contain about 3% hexane.[8] The term hexanes refers to a mixture, composed largely (>60%) of n-hexane, with varying amounts of the isomeric compounds 2-methylpentane and 3-methylpentane, and possibly, smaller amounts of nonisomeric C5, C6, and C7 (cyclo)alkanes. These "hexanes" mixtures are cheaper than pure hexane and are often used in large-scale operations not requiring a single isomer (e.g., as cleaning solvent or for chromatography). Isomers[edit]Main article: C6H14 Common name IUPAC name Text formula Skeletal formula Normal hexane, n-Hexane Hexane CH3(CH2)4CH3 Isohexane 2-Methylpentane (CH3)2CH(CH2)2CH3 3-Methylpentane CH3CH2CH(CH3)CH2CH3 2, 3-Dimethylbutane (CH3)2CHCH(CH3)2 Neohexane 2, 2-Dimethylbutane (CH3)3CCH2CH3 Uses[edit] In industry, hexanes are used in the formulation of glues for shoes, leather products, and roofing. They are also used to extract cooking oils (such as canola oil or soy oil) from seeds, for cleansing and degreasing a variety of items, and in textile manufacturing. They are commonly used in food based soybean oil extraction in the United States, and are potentially present as contaminants in all soy food products in which the technique is used[citation needed]; the lack of regulation by the FDA of this contaminant is a matter of some controversy.[9][10] A typical laboratory use of hexanes is to extract oil and grease contaminants from water and soil for analysis.[11] Since hexane cannot be easily deprotonated, it is used in the laboratory for reactions that involve very strong bases, such as the preparation of organolithiums. For example, butyllithiums are typically supplied as a hexane solution.[12] Hexanes are commonly used in chromatography as a non-polar solvent. Higher alkanes present as impurities in hexanes have similar retention times as the solvent, meaning that fractions containing hexane will also contain these impurities. In preparative chromatography, concentration of a large volume of hexanes can result in a sample that is appreciably contaminated by alkanes. This may result in a solid compound being obtained as an oil and the alkanes may interfere with analysis.