In this activity, students will learn how to name simple organic structures including alkanes, branched alkanes and haloalkanes.
This activity will help prepare your students to meet the performance expectations in the following standards:
- Scientific and Engineering Practices:
- Developing and Using Models
- Obtaining, Evaluating, and Communicating Information
By the end of this activity, students should be able to
- Name simple organic structures based on IUPAC rules for nomenclature.
- Create structural formulas for organic molecules based on a given name.
This activity supports students’ understanding of
- Organic Chemistry
- Molecular Structure
- Naming Compounds
Teacher Preparation: 20 Minutes
Lesson: 60-90 minutes
- 2-3 Ball and Stick Model Sets
- No specific safety precautions need to be observed for this activity.
- This lesson is broken down into four parts. Before the lesson the students should know the different types of chemical structures (condensed, line, etc.).
- I usually teach this lesson after I have gone over types of structures, so you should set structural expectations for your students. Also, this is a good time to review how many bonds carbon makes. Make sure the students are always counting to FOUR!
- In Part A the students look at various organic compounds and look for patterns in the naming of the compounds. This is designed to allow them to discover the rules themselves and make nomenclature a little less intimidating. There are various ways that a teacher can lead this section. For example, they could have the students work in pairs with whiteboards and then have the class do a gallery walk of the “naming rules” each group came up with. Another idea would be to work alone and then just share with the person next to you. Either way, the teacher should have the class come up with a list of rules together at the end. This is also a great time to talk about where students have heard these names in the “everyday world”. Students may have heard words like propane, butane, octane and ethanol.
- In Part B the students get the rules written out for them to keep as “notes”. This is a good time to go over various examples. Some are given in the student section. These should probably be kept from the students until they have completed part A.
- In Part C the students get to practice nomenclature. Again, this can be presented in a variety of ways. The teacher could simply hand the practice out as a worksheet to be done individually. If this is the case, it is always a good idea to have the students check with a partner or two before you go over the answers as a class. It helps them to communicate their ideas and learn from each other. Another idea would be to put the structures on cards and have the students work in small groups to answer each structure on a whiteboard. The teacher can walk around and check answers.
- In Part D the students get to walk around the room and look at five molecular models (ball and stick) of structures. Teachers are free to do this any way they like. I like to set up five structures (two sets of each to make it easier for everyone to see). The students can work alone or in pairs to name the structures. You can also have the students practice drawing their bond line formulas during this section.
- An alternative way that I have done Part D is to give each group of three a molecular model kit and have one student build while the other two name. You can have the students take pictures of their structures and names and post them to a class Google Doc (or something similar) where the rest of the class can check their work.