Vanessa P. Manibpel
De La Salle University - Dasmariñas
ABSTRACT
Five substances namely Hexane, Eugenol, Unknown hydrocarbon 1, Unknown hydrocarbon 2, and Acetylene gas was used for the selective reactivity of hydrocarbons to functional group tests; Bayer’s test, Bromine test light, Bromine test dark, and Tollen’s test. In Bayer’s test, only Acetylene, Eugenol and Unknown hydrocarbon 2 reacted positively and the rest retain the purplish color of KMnO4. On the other hand, the five compounds in Bromine test with light reacted positively. In Bromine test dark, Hexane and Unknown hydrocarbon 1 did not react because light (UV) is absent. Lastly, in Tollen’s reagent, only Acetylene reacted positively and all the other compounds gave a negative result since they are all hydrocarbons. INTRODUCTION
Hydrocarbons are simple organic compounds with a distinct character of having Carbon and Hydrogen atoms only. They are divided into three main categories base on the type of orbital hybridization they have. The three main groups of Hydrocarbons are Alkanes, Alkenes, and Alkynes (1).
Alkanes are sp3-hybridized hydrocarbons characterized by single bonds between carbon atoms included in their chains. Alkanes are also called saturated hydrocarbons because they contain the highest possible H atoms that they can since their single bonds give the Carbon atoms the opportunity to bond with three or two hydrogen atoms. Alkenes on the other hand are sp2-hybridized substances that are distinguished from other hydrocarbons through the presence of double bond/s between its carbon atoms. The third category of hydrocarbons is sp-hybridized Alkynes that have triple bond/s between C atoms. Alkenes and Alkynes, as contrasted to Alkanes, are classified as unsaturated hydrocarbons (1).
In the real world, these single, double, and triple bonding are non-observable since they exist in the molecular level. The answer to identification of hydrocarbons based on
References: (1) McMurry, J. Simanek, E. Fundamentals of Organic Chemistry 6th edition. 2008. Thomson Brooks/Cole. 5 Shenton Way #01-01 UIC Bldg. Singapore. (2) Difference Between Alkanes, Alkenes and Alkynes | Difference Between | Alkanes, Alkenes vs Alkynes http://www.differencebetween.net/science/chemistry-science/difference-between-alkanes-alkenes-and-alkynes/#ixzz2FeMdOJsq (3) Experiment no. 3: Reactions of Hydrocarbons hand-out (4) http://www.britannica.com/EBchecked/topic/108720/chemical-industry/82249/Acetylene