The Difference Between Alkanes, Alkenes, and Alkynes

Chemistry, Education
[caption id="attachment_16044" align="alignright" width="440"] An acetylene (ethyne) torch.[/caption] Alkanes, alkenes, and alkynes are made up of carbon and hydrogen. The carbon atoms in each exhibit a valency of four.  Though these three hydrocarbon varieties are similar, there is a difference in bonding. We illustrate this with the simplest example: ethane vs. ethene vs. ethyne. Common and Scientific Names Common names are names given to many compounds, but they may mislead the uninitiated. For instance, the scientific names of alkenes contain the suffix –en(e) as part of their name. But acetylene is not an alkene. It is an alkyne. The scientific names of alkynes contains the suffix –yne. Acetylene is scientifically named ethyne. Yet, it nomenclature is not the only difference between alkanes, alkenes, and alkynes. Alkanes Alkanes are completely saturated…
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Straight Chain Alkanes: Predicting Properties

Straight chain alkanes are compounds with a non-branched backbone of carbon atoms. In addition, as many hydrogen atoms as possible are attached to each carbon atom. Straight chain alkanes are “saturated” hydrocarbons, which means they are completely filled up with hydrogen. See Figure 1 for examples of straight chain, branched chain, saturated, and unsaturated hydrocarbons. Methylene With the exceptions of methane and ethane, straight chain alkanes differ in the number of methylene groups (CH₂) each contains.  Thus the first five hydrocarbons, methane, ethane, propane, butane, and pentane are written, CH₄ CH₃CH₃ CH₃CH₂CH₃ CH₃CH₂CH₂CH₃ CH₃CH₂CH₂CH₂CH₃ Another method of writing straight chain alkane chemical formulas for the butane and pentane structures above is, CH₃(CH₂)₂CH₃ CH₃(CH₂)₃CH₃ General Formula From this, we can formulate the rule for the formula of a straight chain alkane…
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