There are three chemical properties will be discussed which are combustion, reaction with bromine and reaction with potassium permanganate. Combustion was used to test the unsaturation of hydrocarbon. The degree of unsaturation refers to the number of the rings and / or multiple bonds present in the hydrocarbon molecule (McMurry, 2015). Hexane was a saturated hydrocarbon, it completely combusted and emitted carbon dioxide plus water. Cyclohexene was an unsaturated hydrocarbon, it undergoes incomplete combustion (Clark, 2003) which showed the great intensity of light compared to hexane due to the higher ratio of carbon and hydrogen in cyclohexene. Black smoke that released during combustion of toluene indicated its aromatic identity. …show more content…
Unknown A behave like alkane group that produced a clean flame and undergoes complete combustion to release carbon dioxide and water, while unknown B behave like alkene sustains incomplete combustion which produced a dirty flame that has more intensity of light and shoot.
Next, reaction with bromine was a common application of halogenation. Hexane will react with bromine only under the free radical condition which indicate must expose to the sunlight as this is a photochemical reaction. With the presence of sunlight, a bromine atom replaced one of the hydrogen atoms in the hexane to form alkyl halide. Hydrogen bromide which is one of the products of the substitution reaction turns blue litmus paper into red as hydrogen bromide was acidic. In the dark, hexane does not react with bromine due to there are absent of multiple bonds. Hexane only has carbon-carbon single bond. Cyclohexene was more reactive compared to hexane as it is an unsaturated hydrocarbon which reacts to bromine rapidly no matter in the dark or with …show more content…
There are a few precautionary steps need to take into consideration when handling this practical. First, the organic compounds used in this practical are highly volatile and flammable, it should not use near to the flame. All the addition of organic compound process should be performed in the hood. Second, we should wear gloves and do the addition of bromine in the hood, as bromine vapour can be irritating. When dealing with bromine solution, we should also avoid spilling toward our hand as bromine was a strong oxidising agent. Third, the combustion experiment must be performed in the hood. Last but not least, all the organic waste was disposed into an appropriate waste container in the hood rather than just pour it into the