An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming rings.Alkanes have all single bonds, alkenes have a C C double bond, and alkynes have a C C triple bond. 3. Indicate whether each molecule is an aliphatic or an aromatic hydrocarbon; if aliphatic, identify the molecule as an alkane, an alkene, or an alkyne.
11 Some Reactions of Hydrocarbons Experiment #2 Objective: To distinguish alkanes, alkenes and aromatic hydrocarbons by their chemicalreactions and reactivity. Introduction Hydrocarbons are organic compounds containing carbon and hydrogen.  1.Alkanes are saturated hydrocarbons; meaning a single bond between the carbon atoms; alkenes are unsaturated hydrocarbons meaning one or more double bonds between carbon atoms; alkynes are also unsaturated hydrocarbons with one or more triple bonds between the carbon atoms. Alkanes are saturated hydrocarbons which mean they are compounds with a single bond between the atoms. Saturated hydrocarbons are saturated with hydrogen and are the simplest. They are represented in general as CnH2n+2 in case of non-cyclic structures or straight-chain structures. They are also called paraffins. In organic chemistry, an alkene is an unsaturated hydrocarbon that contains at least one carbon –carbon double bond. Alkene, olefin, and olefine are used often interchangeably (see nomenclature section below). Acyclic alkenes, with only one double bond and no other functional groups, known as mono-enes, form a homologous series of hydrocarbons with the general formula C n H 2n. Alkenes have two hydrogen atoms less than the corresponding alkane (with the same number of carbon atoms). Alkanes, Alkenes vs Alkynes. Alkanes, alkenes and alkynes are all hydrocarbons with different structures and thus different physical and chemical properties. Hydrocarbons. In the study of organic chemistry, the organic compounds which are made up of carbon and hydrogen are called hydrocarbons. Alkanes are saturated hydrocarbons which mean they are compounds with a single bond between the atoms. Saturated hydrocarbons are saturated with hydrogen and are the simplest. They are represented in general as CnH2n+2 in case of non-cyclic structures or straight-chain structures. They are also called paraffins. There are four classifications of hydrocarbons; saturated hydrocarbons or alkanes, unsaturated hydrocarbons or alkenes and alkynes, cycloalkanes, and aromatic hydrocarbons or arenes. Alkanes. Alkanes are saturated hydrocarbons which mean they are compounds with a single bond between the atoms. Saturated hydrocarbons are saturated with hydrogen and are the simplest. They are represented in general as CnH2n+2 in case of non-cyclic structures or straight-chain structures. They are also called paraffins. A hydrocarbon that contains no double bonds is called an alkane, or hydrocarbon containing only single bonds. Methane and ethane are both alkanes. For each element of unsaturation, which is a ring or double bond in a molecule, the total number of hydrogens in the hydrocarbon will decrease by two. Hydrocarbons with carbon-carbon double bonds are called alkenes. Hydrocarbons with carbon-carbon triple bonds are called alkynes. And hydrocarbons that contain rings of carbon atoms that are joined by alternating single and double bonds are called aromatic. An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming rings. The configuration of six carbon atoms in aromatic compounds is known as a benzene ring, after the simplest possible such hydrocarbon, benzene. Aromatic hydrocarbons can be monocyclic (MAH) or polycyclic (PAH). Alkanes have all single bonds, alkenes have a C C double bond, and alkynes have a C C triple bond. 3. Indicate whether each molecule is an aliphatic or an aromatic hydrocarbon; if aliphatic, identify the molecule as an alkane, an alkene, or an alkyne. The simplest organic compounds are hydrocarbons and are composed of carbon and hydrogen. Hydrocarbons can be aliphatic or aromatic; aliphatic hydrocarbons are divided into alkanes, alkenes, and alkynes. The combustion of hydrocarbons is a primary source of energy for our society. Hydrocarbons with only CC single bonds are known as saturated hydrocarbons. If a hydrocarbon contains double and/or triple bonds, it is known as unsaturated. The molecule ethylene (C H) contains a carbon double bond and is officially referred to as ethene, although the name ``ethylene'' is more commonly used. 
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how do aromatic hydrocarbons differ from alkenes