Difference Between Hexane And Toluene

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Combustion, a chemical reaction between substances, usually including oxygen and usually accompanied by the generation of heat and light in the form of flame. The hydrocarbons become harder to ignite as the molecules get bigger. Combustion of alkanes with bigger molecule will produce more soot as the percentage of carbon of the molecule is higher. The amount of soot produced depends on the percentage of carbon in a hydrocarbon molecule. Hexane and cyclohexene produced very small of light soot due to smaller compound compared to toluene. Aromatic compounds like toluene are high in carbon content and slow to be oxidized. Some of the carbon atoms are converted into elemental carbon in the heat, but escape the flame before they are attacked by …show more content…
Presence of ultra-violet light or flame, the alkanes will undergo substitution reaction with halogens. For instance, in UV light, hexane reacts with halogen molecules such as bromine and produce 1-bromohexane. This reaction is a substitution reaction because one of the hydrogen atoms from the hexane is replaced by a bromine atom. The presence of the C=C double bond allows alkenes to react in both light and dark environment. The reaction between bromine and alkenes is an example of a type of reaction called a free radical substitution. The bromine is decolourised because a colourless dibromo compound forms. From the experiment, cyclohexene react with bromine to form 1,2-dibromocyclohexene. In the first stage of the reaction, one of the bromine atoms becomes attached to both carbon atoms, with the positive charge being found on the bromine atom. A bromonium ion is formed. (Jim, 2000)
In dark, toluene does not react with bromine except with the presence of catalyst (Iron(III) chloride) but react with bromine in light. The reaction much similar to alkane but only the position of the bromine atom being
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Alkene produced less soot as cyclohexene. It can react with bromine as it has a double bond. The anti-addition occurred during the reaction which means the bromine molecules added to the opposite side of the double bond. Alkene also react with potassium permanganate. The brown precipitate formed after the reaction was manganese(IV) oxide. While for unknown B, it was possible to be an alcohol. Alcohol released a lot of the soot during combustion. It does not react with bromine due to absent of carbon-carbon double bond. Primary and secondary alcohol can react with potassium permanganate to form aldehyde or ketone but not tertiary as it does not have hydrogen that attached to carbon. When the primary or secondary alcohol reacted, the solution is decolourised and brown precipitate (manganese dioxide) was

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