Unit 4: Chemical Bonding

How do the structures of molecules determine bulk properties?

About

Unit 4 Contents

A. Unit Resources
B. Unit Information
C. Standards & Practices
D. Task Sets

1 - Unit Opener
2 - Intramolecular Forces
3 - Molecule Structures
4 - A Property of Smells
5 - Intermolecular Forces
6 - Engineering Project
7 - Assessment

Unit Outcome

Use data and models to describe the types and properties of chemical bonds, to inform the formulas of substances, to predict intermolecular forces, and to explain macro-level physical properties of substances.

Anchoring Phenomenon

Chemists use and design materials that utilize the properties of molecules to solve problems. (Use a phenomena to open the unit that matches the engineering project you do at the end. Examples: different candies are made of sugar but taste and feel different, soaps and detergents come in many different varieties to tackle stains or clean surfaces, the properties of cosmetics such as chapstick)

Essential Question

How do the structures of molecules determine bulk properties?

Unit 4 Planner

The Unit 4 Planner Google Doc can be accessed using the link above or you can scroll down to see the entire Unit Plan by scrolling down.

How is the Unit Structured?

Unit 4 contains 7 task sets which will take approximately 12 90-minute class periods to complete. Essential Questions and Phenomenon for the seven learning tasks of this unit are found in the Unit 4 Walkthrough. 

Unit Resources

Open Access Unit 4

  • This Google folder (English) - houses all documents for this unit that have been updated.

  • Google folder (Spanish) - coming soon

Student Interactive Notebook

Vocabulary List

These are the vocabulary terms used and discussed in the unit.

Rubric

This is the rubric for Unit 4 and lives in the restricted folder.

Unit Information

  • The following are example options to extend parts of the unit to deepen students’ understanding of science ideas:

  • Task Set 1

    • Students generate questions related to the chosen material that will anchor the unit (e.g. candy, chapstick, soap, stain remover)

    Task Set 2

    • Students collect data on their assigned property for a range of chemicals (melting point, conductivity, or solubility). They then analyze the data and write a conclusion about the patterns they found for different types of compounds/molecules.

    Task Set 3

    • Students accurately determine the charges of ions, how many ions come together to form a particular compound, and name ionic compounds. Students can explain the relationship between ions and their periodic table group.

    Task Set 4

    • Students collect data related to smells so they can make data informed predictions about how the arrangement of atoms in a molecule affect its 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. [Clarification Statement: Emphasis is on understanding the strengths of forces between particles, not on naming specific intermolecular forces (such as dipole-dipole). Examples of particles could include ions, atoms, molecules, and networked materials (such as graphite). Examples of bulk properties of substances could include the melting point and boiling point, vapor pressure, and surface tension.] [Assessment Boundary: Assessment does not include Raoult’s law calculations of vapor pressure.]

    • Unit 4 Chemical Bonding Unit Test

    HS-PS2-6: Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.* [Clarification Statement: Emphasis is on the attractive and repulsive forces that determine the functioning of the material. Examples could include why electrically conductive materials are often made of metal, flexible but durable materials are made up of long chained molecules, and pharmaceuticals are designed to interact with specific receptors.] [Assessment Boundary: Assessment is limited to provided molecular structures of specific designed materials.]

    • Unit 4 Chemical Bonding Unit Test

Standards & Practices

  • This unit builds toward the following NGSS performance Expectations (PE’s). Links to evidence statements are provided:

    • 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. [Clarification Statement: Emphasis is on understanding the strengths of forces between particles, not on naming specific intermolecular forces (such as dipole-dipole). Examples of particles could include ions, atoms, molecules, and networked materials (such as graphite). Examples of bulk properties of substances could include the melting point and boiling point, vapor pressure, and surface tension.] [Assessment Boundary: Assessment does not include Raoult’s law calculations of vapor pressure.]

    • HS-PS2-6: Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.* [Clarification Statement: Emphasis is on the attractive and repulsive forces that determine the functioning of the material. Examples could include why electrically conductive materials are often made of metal, flexible but durable materials are made up of long chained molecules, and pharmaceuticals are designed to interact with specific receptors.] [Assessment Boundary: Assessment is limited to provided molecular structures of specific designed materials.]

  • This unit contains these Life Science Grade 9-12 DCI elements.

    • PS1.A: Structure and Properties of Matter

      • The structure and interactions of matter at the bulk scale are determined by electrical forces within and between atoms.

    • PS2.B: Types of Interactions

      • Attraction and repulsion between electric charges at the atomic scale explain the structure, properties, and transformations of matter, as well as the contact forces between material objects

  • This unit focuses on these Science and Engineering Practices

    • Planning and Carrying out Investigations Planning and carrying out investigations in 9-12 builds on K-8 experiences and progresses to include investigations that provide evidence for and test conceptual, mathematical, physical, and empirical models.

      • Plan and conduct an investigation individually and collaboratively to produce data to serve as the basis for evidence, and in the design: decide on types, how much, and accuracy of data needed to produce reliable measurements and consider limitations on the precision of the data (e.g., number of trials, cost, risk, time), and refine the design accordingly.

    • Obtaining, Evaluating, and Communicating Information Obtaining, evaluating, and communicating information in 9–12 builds on K–8 and progresses to evaluating the validity and reliability of the claims, methods, and designs. Communicate scientific and technical information (e.g., about the process of development and the design and performance of a proposed process or system) in multiple formats (including oral, graphical, textual and mathematical).

  • This unit contains these Crosscutting Concepts

    • Patterns

      • Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

    • Structure and Function

      • Investigating or designing new systems or structures requires a detailed examination of the properties of different materials, the structures of different components, and connections of components to reveal its function and/or solve a problem.