Hydrocarbons - Alkenes

Question 1

Alkenes

Answer 1

• hydrocarbons with at least one double bond, can be straight chain, branchd, or in a ring (cyclic)
• unsaturated hydrocarbon because carbons involved in double bond are only connected to three other atoms

Question 2

Nomenclature of Alkenes

Answer 2

1. find the longest chain of carbon atoms that contains the double bond to establish the parent name

Add -ene to root name

2. number the chain so that the carbons of the double bond are given the lowest numbers possible

Question 3

Nomenclature for CycloAlkenes

Answer 3

1. count number of carbon atoms in ring and add prefix cyclo- to parent alkene name
2. the ring is numbered to give the double bond the lowest possible numbers ( in the case of a cycloalkene this is always the numbers 1 and 2)

Question 4

Name the following alkene:

CH3CH=CHCH2CH3

Answer 4

2-pentene