10.4 – NOTES Beyond Alkanes

C.3 Beyond Alkanes Saturated hydrocarbons Each carbon atom forms as many single covalent bonds as it can All alkanes are saturated molecules Points of unsaturation Double bonds have 1 point(s) of unsaturation Triple bonds have 2 point(s) of unsaturation Rings have 1 point(s) of unsaturation

Alkenes Hydrocarbon with at least 1 double bond   Unsaturated hydrocarbons More chemically reactive than alkanes because they are able to break the double bond to bond with other atoms General formula- CnH2n

Naming 1. count the number of carbons to determine prefix 2. add the suffix – ene 3. determine the location of the double bond (must be lowest number) *Ethene and propene will not require a number as the double bond will be on the first carbon. 4. examples:  

Substituted alkenes They contain one or more other atoms besides C and H O, N, Cl, S Changes reactivity Two different substituted alkenes may share molecular formulas, but the arrangement/structural formula of the molecule may be very different

Lab involving alkenes and basic substituted alkenes Alkynes C.4 The Builders Lab involving alkenes and basic substituted alkenes Alkynes Hydrocarbon with a triple bond   General formula- CnH2n-2

Naming 1. count the number of carbons to determine prefix 2. add the suffix –yne 3. determine the location of the triple bond (must be lowest number) *ethyne and propyne will not require a number as the triple bond will be on the first carbon. 4. examples:

Dimer Structure made from 2 monomers Formed by breaking a double bond

C.5 More Builder Molecules Some carbons are joined in rings, rather than in straight lines Cycloalkanes Saturated hydrocarbons made of singly bonded carbons in a ring form   General formula- CnH2n

Naming 1. determine the number of carbons and corresponding prefix 2. place cyclo- in front 3. add suffix –ane 4. examples:  

Aromatic compounds Aromatics involve double bonds within the ring Behave like they DON”T have double bonds- not reactive like noncyclical double bonded compounds Discovered that the double bond is shared among all carbons equally. Shown with a circle in the center representing the double bonding Very different from cycloalkanes The most common aromatic compound is benzene, C6H6 Structure (next slide)      Uses: perfumes, dyes