Summary

In this project, students will research a molecule selected from the teacher approved list, construct a three-dimensional model of the molecule, and present their research to the class in a 7-10 minute oral presentation.

Grade Level

High School

NGSS Alignment

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

• HS-PS1-1: Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
• HS-PS1-2: Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
• HS-PS1-3: Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.
• HS-PS1-7: Use mathematical representation to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.
• 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
  • Analyzing and Interpreting Data
  • Obtaining, Evaluating, and Communicating Information

Objectives

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

• Describe and understand their molecule’s:
  • Name and chemical formula
  • Industrial and/or consumer uses
  • Chemical and physical properties (i.e. melting/boiling point, density, molar mass, reactivity, etc.)
  • Synthesis reaction, including possible by-products
  • Possible environmental issues
• Draw their molecule’s Lewis Structure including all bonding and nonbonding electrons
• Determine their molecule’s VSEPR shape with corresponding bond angle(s)
• Analyze their molecule’s dipole moments to determine overall molecular polarity
• Create a PowerPoint or Prezi presentation from gathered research information
• Construct a three-dimensional model of their molecule including:
  • All bonding and nonbonding electrons
  • Atoms built to relative scale in terms of atomic radius
  • Bonds built to relative scale in terms of bond length of single, double, or triple bonds
  • Bond angles built to relative scale in terms of VSEPR shape
  • The base that the model is mounted on must be decorated to reflect the molecule’s uses
• Explain all of the pertinent information about their molecule in a 7-10 minute oral presentation

Chemistry Topics

This project supports students’ understanding of:

• Molecules and Bonding
• Covalent Bonding
• Lewis Structures
• VSEPR Shapes
• Electronegativity
• Polarity
• Atomic Structure
• Atomic Radius
• Valence Electrons

Time

Teacher Preparation: 30-60 minutes

Lesson: 30 minutes in class, and 3 weeks outside of class

Materials

• Project assignment handouts
• Molecule sign-up sheets with teacher approved molecules
• Optional: one example of the three-dimensional model
• Optional: one example of the PowerPoint or Prezi presentation

Safety

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

Teacher Notes

• Possible teacher-approved molecules: NH ₃, HOCl, HNO₃, C₂H₂, CHCl ₃, CCl₄, H₂O₂, CH₃OH, CO ₂, CH₄, H₂S, CS₂, O₃,. Recommended for Honors Level only: C ₂H₄, H₂CO₃, NO ₂, H₂SO₄, N₂O, N₂H_4.
• Teacher may want to create an example or have a previous student example of project including three-dimensional model and/or PowerPoint or Prezi presentation. Note that this will cause the “Teacher Preparation Time” indicated above to be longer.
• Teacher may or may not want to use the sample rubric shown in the student handout.
• The 30 minute in-class time frame is for the teacher to explain and introduce the project. If a teacher wants to give more in-class time to work on the project, then he or she may do so.
• Teachers can decide whether they want students to work alone or in a group. If students are going to work in a group, it is suggested that the group should be no larger than three total people and that these students are friends so that they can easily get together outside of school to work on the project (especially if no in-class time is being provided).
• Students are required to provide their own supplies (unless the teacher or school wants to contribute).
• It is optional whether or not the teacher wants to check-in with the students and/or require a draft to be turned in during the three week time frame.
• The website for Prezi is: http://www.prezi.com.
• Allow for 7-10 minute presentations per group (groups of 1-3).
• Sample model projects: