Naming Hydrocarbons

Hydrocarbons:  Compounds containing only hydrogen and carbon

Determine the molecular formula from the structure:  Compare the following hydrocarbons which each have three carbons.  Count the number of atoms of each element (carbon is gray, hydrogen is white) to determine the molecular formula.  Click the box to check your answer.

Name propane propene propyne
structure

 

 

molecular

formula

 

 

 

Determine the bond types:  Looking at the structures above, determine the bond types for each compound.  Click to check you answers.  Then determine the suffix (ending) for each name, click to check your answer.  Finally, click to reveal the hydrocarbon type.

  propane propene propyne
maximum bond type
suffix
hydrocarbon type

Focus on number of Carbons:  The table below shows the prefixes which are used to show how MANY carbons are in the compound.

# of carbons 1 2 3 4 5 6 7 8 9 10
prefix meth- eth- prop- but- pent- hex- hept- oct- non- dec-

To name the hydrocarbon, you must add the prefix for the number of carbons to the suffix for the maximum bond type.  Three examples are shown in the table below.  Try to name the other six and click to check your answers.

# of carbons alkane

(only single bonds!)

alkene

(at least one double bond)

alkyne

(at least one triple bond)

 

2

 

eth-  +  -ane

=  ethane

 

4

 

but- + -ene

= butene

 

7

 

hept- + -yne

= heptyne

Your Turn!  Determine the molecular formula and name the following molecules. ( The answers are not given!)  Turn in for a grade.

Problem #1                                                                Problem #2

                                                    

 

 

 

Problem #3                                                                Problem #4

                                                

 

 

 

 

Created by Mary Alice Adah        Watkins Mill High School, Gaithersburg, MD          6/2003

(note:  this is my first web page ever)

Return to Modeling and Visualization in Chemistry Workshop webpage.