« Return to AACT homepage

AACT Member-Only Content

You have to be an AACT member to access this content, but good news: anyone can join!

Need Help?

Introduction to Functional Groups Mark as Favorite (10 Favorites)

ACTIVITY in Polarity, Molecular Structure , Functional Groups. Last updated January 30, 2024.

Summary

In this activity, students will learn about the naming conventions for organic compounds and examine the functional groups of different molecules.

Grade Level

High School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

  • HS-PS2-6: Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.
  • Scientific and Engineering Practices:
    • Developing and Using Models
    • Obtaining, Evaluating, and Communicating Information

Objectives

By the end of this activity, students should be able to:

  • Differentiate between the naming rules for various organic molecules.
  • Determine the polarity of organic molecules.
  • Identify the intermolecular forces between organic molecules.
  • Identify electron-rich areas of organic molecules to prepare students for drawing mechanisms.

Chemistry Topics

This activity supports students’ understanding of:

  • Organic Chemistry
  • Functional Groups
  • Molecular Structure
  • Polarity

Time

Teacher Preparation: 20 minutes
Lesson: 60 minutes

Materials

  • Student handout

Safety

  • No specific safety precautions need to be observed for this activity.

Teacher Notes

  • Consider having a small lecture on the naming of organic compounds before handing out this worksheet. While naming isn’t something that students need to master, the naming conventions given in the chart are simple and may require more explanation.
  • Teachers may find it helpful to first use the activities Modeling Carbohydrates and Naming Alkanes to help students develop a foundational understanding before considering functional group differences.
  • Students will need a good foundation of Lewis dot structures, molecular structures, polarity, and intermolecular forces before attempting the questions on this worksheet.
  • If your students have never seen a skeleton model, explain where the carbon and hydrogen atoms would be in these simplified structures.

For the Student

Introduction

Many careers in chemistry and medical sciences require understanding of organic chemistry, including the naming systems, organic reactions, and interactions between molecules. In this activity, you will be introduced to some of the basics of organic chemistry as well as functional groups.

Part I: Naming Conventions

    1. Look at the organic structures in the “example” column of the table above.
      1. What is the meaning of the prefix “pent”?
      2. What is the meaning of the prefix "prop”?
      3. What is the meaning of the prefix "eth”?
    2. Make a list of the prefixes for organic naming below for chains of carbons 1-10 in length:

    Part II: Exploration

    1. Functional Groups Sorting: Using the examples given in the nomenclature chart, draw the general structures of all organic compounds that are polar.
    2. Comparison: Draw an alcohol that has 4 carbon atoms next to a carboxylic acid that has 3 carbon atoms. Write the name below the structure. Identify at least one similarity and one difference.
    3. Application:
      1. Determine and write the chemical formula of the structure below.
      2. Circle the part(s) of the structure that contain carboxylic acid.
      3. Research citric acid. What can it be used for? How do the carboxylic acid groups explain some of its properties?
    1. Memory Master: Create two mnemonic devices to help you remember the structure of two functional groups.
    2. Apply It! Place the functional groups listed below in order of time of evaporation (assuming that they each are part of a parent chain with the same number of carbon atoms). The functional group that would have the lowest boiling point comes first. Explain your answer.
      1. Ether
      2. Alkane
      3. Amide
      4. Carboxylic Acid
    3. Naming Practice: Match the compound with the correct name.
    1. Taking it Further: The study of organic chemistry involves showing the movement of electrons that occurs during an organic reaction. One step that prepares you for this is identifying the electron-rich area of a molecule. Circle the electron-rich area of the molecule below. Explain why that area is the most electron-rich.