The unit builds toward the following NGSS Performance Expectations (PE):

• 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-PS2-6*: Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.
• HS-ESS1-2†: Construct an explanation of the Big Bang theory based on astronomical evidence of light spectra, motion of distant galaxies, and composition of matter in the universe.
• HS-ESS2-1†: Develop a model to illustrate how Earth’s internal and surface processes operate at different spatial and temporal scales to form continental and ocean-floor features.
• HS-ESS2-5: Plan and conduct an investigation of the properties of water and its effects on Earth materials and surface processes.

*This performance expectation is developed across multiple units. This unit reinforces and fully develops these NGSS PEs from a prior OpenSciEd chemistry unit.

†This performance expectation is developed across multiple courses. This unit works toward these NGSS PEs that students will fully develop in the OpenSciEd physics course.

PS1.A: Structure and Properties of Matter

• Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons. (HS-PS1-1)
• The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states. (HS-PS1-1, HS-PS1-2)
• The structure and interactions of matter at the bulk scale are determined by electrical forces within and between atoms. (HS-PS1-3, HS-PS2-6)

PS1.B: Structure and Properties of Matter

• The fact that atoms are conserved, together with knowledge of the chemical properties of the elements involved, can be used to describe and predict chemical reactions. (HS-PS1-2)

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. (HS-PS1-1, HS-PS1-3, HS-PS2-6)

PS4.B: Electromagnetic Radiation

• Atoms of each element emit and absorb characteristic frequencies of light. These characteristics allow identification of the presence of an element, even in microscopic quantities. (secondary) (HS-ESS1-2)

ESS1.A: The Universe and Its Stars

• The study of stars’ light spectra and brightness is used to identify compositional elements of stars, their movements, and their distances from Earth.(HS-ESS1-2, HS-ESS1-3)
• The Big Bang theory is supported by observations of distant galaxies receding from our own, of the measured composition of stars and non-stellar gasses, and of the maps of spectra of the primordial radiation (cosmic microwave background) that still fills the universe. (HS-ESS1-2)
• Other than the hydrogen and helium formed at the time of the Big Bang, nuclear fusion within stars produces all atomic nuclei lighter than and including iron, and the process releases electromagnetic energy. Heavier elements are produced when certain massive stars achieve a supernova stage and explode. (HS-ESS1-2, HS-ESS1-3)

ESS2.A: Earth Materials and Systems

• Earth’s systems, being dynamic and interacting, cause feedback effects that can increase or decrease the original changes. A deep knowledge of how feedbacks work within and among Earth’s systems is still lacking, thus limiting scientists’ ability to predict some changes and their impacts.(HS-ESS2-1, HS-ESS2-2)

ESS2.B: Plate Tectonics and Large-Scale System Interactions

• Plate tectonics is the unifying theory that explains the past and current movements of the rocks at Earth’s surface and provides a framework for understanding its geologic history. Plate movements are responsible for most continental and ocean-floor features and for the distribution of most rocks and minerals within Earth’s crust. (HS-ESS2-1)

ESS2.C: The Roles of Water in Earth’s Surface Processes

• The abundance of liquid water on Earth’s surface and its unique combination of physical and chemical properties are central to the planet’s dynamics. These properties include water’s exceptional capacity to absorb, store, and release large amounts of energy, transmit sunlight, expand upon freezing, dissolve and transport materials, and lower the viscosities and melting points of rocks. (HS-ESS2-5)

This unit intentionally develops students’ engagement in these practice elements:

Developing and Using Models

• Evaluate merits and limitations of two different models of the same proposed tool, process, mechanism or system in order to select or revise a model that best fits the evidence or design criteria.
• Develop, revise, and/or use a model based on evidence to illustrate and/or predict the relationships between systems or between components of a system.
• Develop and/or use multiple types of models to provide mechanistic accounts and/or predict phenomena, and move flexibly between model types based on merits and limitations.

Obtaining, Evaluating, and Communicating Information

• Critically read scientific literature adapted for classroom use to determine the central ideas or conclusions and/or to obtain scientific and/or technical information to summarize complex evidence, concepts, processes, or information presented in a text by paraphrasing them in simpler but still accurate terms.
• Compare, integrate, and evaluate sources of information presented in different media or formats (e.g., visually, quantitatively) as well as in words in order to address a scientific question or solve a problem.
• Evaluate the validity and reliability of and/or synthesize multiple claims, methods, and/or designs that appear in scientific and technical texts or media reports, verifying the data when possible.
• Communicate scientific and/or technical information or ideas (e.g., about phenomena and/or the process of development and the design and performance of a proposed process or system) in multiple formats (including orally, graphically, textually, and mathematically).

Elements from the following practices are also key to the sensemaking in this unit:

• Using Mathematics and Computational Thinking
• Constructing Explanations and Designing Solutions

This unit intentionally develops students’ use of  these crosscutting concept elements.

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.
• Classifications or explanations used at one scale may fail or need revision when information from smaller or larger scales is introduced; thus requiring improved investigations and experiments.
• Mathematical representations are needed to identify some patterns.
• Empirical evidence is needed to identify patterns.

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.
• The functions and properties of natural and designed objects and systems can be inferred from their overall structure, the way their components are shaped and used, and the molecular substructures of its various materials.

The following crosscutting concepts are also key to the sensemaking in this unit:

• Energy and Matter

Which elements of NOS are developed in the unit?

• Scientific Knowledge Assumes an Order and Consistency in Natural Systems
• Scientific knowledge is based on the assumption that natural laws operate today as they did in the past and will continue to do so in the future. (HS-ESS1-2)
• Science assumes the universe is a vast single system in which basic laws are consistent.

How are they developed?

• In Lesson Set 1, students systematically apply long-term thinking about water’s role on Earth with the assumption that water will behave today in the stream table as it has for thousands or even millions of years on Earth and Mars’ surfaces. The operation of water’s polarity functions the same on Mars as on Earth because the universe is a single system with laws that work consistently: polarity, intermolecular forces, and intramolecular forces.

For the anchoring phenomenon, students critically view the Artemis launch video from NASA and develop models for how humans might make the needed resources to survive beyond Earth, such as water, food, and shelter. The frame of “substances for survival” allows students to zoom in on the elements and the compounds they form, especially water, and build simple reactions as specified in HS-PS1-2. Students also showed high interest in this question across racial and gender identities and their location (rural/urban) in a survey we conducted in pilot states.

The search for elements to survive off Earth anchoring phenomenon was chosen from a group of phenomena aligned with the target performance expectations based on the results of a survey administered to students from across the country and in consultation with external advisory panels that include teachers, subject matter experts, and state science administrators. Search for elements and knowing how they might be engineered to survive off Earthwas chosen for the following reasons:

• Teachers and administrators saw high relevance to current events related to outer space tourism and travel.
• Explaining the interactions involved in resourcing human’s survival in space addresses the selected pieces of DCIs in this bundle at a high school level.
• Students can investigate the interactions of materials with “planetary” surfaces in a scaled-down way in the classroom.
• Major social considerations around space travel invite science-based answers that drive the unit, such as, “Can humans source the things we’d need to survive off of Earth?”

This unit is the third in the OpenSciEd High School Chemistry course sequence. In the second unit of OpenSciEd HS Chemistry, students developed ideas around electrostatics. This unit is designed to build on student’s ideas about the structure of matter, with an emphasis on the formation of covalent bonds, polarity, the periodic table, and the structure of molecules. It also contributes to core ideas for Earth and space science, especially the interactions of water with Earth’s surface.

While HS-ESS2-5 and HS-PS1-2 are addressed in this unit alone in the OpenSciEd High School course sequence, many of the Performance Expectations (PEs) in this unit are shared across other Chemistry or Physics units.

• HS-PS1-1, HS-PS1-3, and HS-PS2-6 are shared with the unit taught just before this one, OpenSciEd Unit C.2: What causes lightning and why are some places safer than others when it strikes? (Electrostatics Unit).
• HS-ESS1-2 is shared with OpenSciEd Unit P.6: Earth’s History and the Big Bang (Cosmology Unit)
• HS-ESS1-1 is shared with OpenSciEd Unit P.2: How forces in Earth’s interior determine what will happen to its surface? (Earth’s Interior Unit)

The unit is organized into four lesson sets. Lesson Set 1 (Lessons 1-5) focuses on answering the question: How can we find water and other substances we need to survive on other objects in space? Students investigate planetary surface features (Earth’s and Mars’) to investigate water and its unique structure and function in erosion. They also develop understandings around physical science concepts of light and matter along with Earth and space science concepts of spectroscopy as a way to identify substances off of Earth. Lesson Set 2 (Lessons 6-9) focuses on answering the question: Why do we need certain types of atoms to create the substances we need? Students develop science ideas about the structure of atoms, the patterns in their bonds, the organization of the periodic table, electronegativity, bond character, and how these affect the polarity and properties of the molecule. Lesson Set 3 (Lessons 10-12) focuses on answering the question: How can we make the substances we need to survive off of Earth using the existing matter in the solar system? Students develop and apply the idea of conservation of matter through chemical equations in the context of a variety of substances, including those that form ionic compounds and form polyatomic ions. Lesson Set 4 (13-15) focuses on answering the question: How can we be more sustainable in what we use and produce? Students consider applications of ideas students figured out to issues related to sustainability, both off Earth and on it. Students investigate what makes a substance recyclable and how to alter the chemical structure of molecules to yield particular properties. Students apply these ideas in a transfer task in Lesson 15. The unit culminates by instilling hope in students that the direction of future research (and careers) in science and engineering, can lead to more sustainable approaches to the way we live and work in the future.

This is the third unit of the High School Chemistry Course in the OpenSciEd Scope and Sequence. We have assumed a traditional sequencing of OpenSciEd Biology, then Chemistry, then Physics. Given this placement, the following modifications would be needed if students do not take OpenSciEd Biology first, or if the Chemistry Course is taught out of order. These include the following adjustments:

• OpenSciEd Unit C.2: What causes lightning and why are some places safer than others when it strikes? (Electrostatics Unit) is critical for supporting the thinking of forces in these bonds. If that unit is not taught first, you may review the nature of charges in an atom using common static electricity phenomena. This unit assumes familiarity with “opposites attract” thinking, charges, and electricity, especially that electrons “jump” or move during ionization. This unit also assumes that students have some experience with protons, neutrons, electrons, and the characteristics of ionic bonding (e.g., positive and negative charges attracting, the formation of ionic compounds/salts). They will construct and organize the periodic table in this unit.
• If taught as part of an AP Chemistry course, you may provide students with additional examination of novel Lewis diagrams, resonance, VSEPR, and bond hybridization, intermolecular forces, and mass/photoelectron spectrometry that are outside the bounds of the NGSS. This unit provides important foundational force and structure-based models so that teaching these concepts should be considerably easier for students once they have a strong understanding of intermolecular forces and the continuum of bond character.
• If used as part of an Earth and space science course, you may want to consider how Lesson Set 2 can be adjusted or shortened, as it focuses on the periodic trends and periodic table. You may extend Lesson Set 1 to include deeper exploration of the Earth’s water-based and plate-based features.

Note that the Haber Process is not considered an appropriate extension during this unit because it is a focal reaction in OpenSciEd Unit C.4: Why are oysters dying, and how can we use chemistry to protect them? (Oysters Unit).

The following are example options to shorten or condense parts of the unit without eliminating important sensemaking for students:

• Lessons 13 and 14 could be removed if students do not bring up recycling.
• Lesson 13: If you are short on time, you could reduce the length of the lesson by removing the videos.

To extend or enhance the unit, consider the following:

• Lesson 2: Have students engage with Station 6 data using CODAP.
• Lesson 2: If students show interest in comparing the properties of water to the properties of other materials they have studied in Electrostatics Unit, take time to co-create a parallel poster.
• Lesson 2: If students are interested in learning more about other potential food sources, Thinking About Aquaculture, is included. Since it mentions the existence of water oceans on some moons in our solar system, this handout may be placed after Lesson 4 or with Lesson 11.
• Lesson 2: Lead students through thinking about the water requirements for astronauts on past missions, such as Apollo 11, then extrapolate to how much humans would need daily to survive off of Earth. This would also have students incorporate CCSS.MATH.CONTENT.HSN.Q.A.1: Use units as a way to understand problems and to guide the solution of multi-step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.
• Lesson 10: Consider demonstrating the cleaning process described in Cleaning Metal-Contaminated Water.
• Lesson 12: If students show interest in researching an additional location in the solar system, additional links are provided.
• Lesson 12: Provide students access to the open access chemical research paper describing the extended molecular structure of cement.
• Lesson 13: More carefully examine recycling in your own community. Have students examine local recycling policies and practices to determine if there are improvements to be made. You may invite someone from the city or county waste system as a guest speaker.
• Lesson 14: If students are interested in materials other than ceramics (like concrete) or polymers, such as metals, electronic materials, or composites, you may wish to have them research these materials using Synthesis and Evaluation.
• Lesson 15: Consider having students balance additional chemical equations beyond main group elements and combustion reactions (NGSS Assessment Boundary).

• Nicole Vick, Unit Co-Lead, Northwestern University
• Michael Novak, Revision Unit Co-Lead, Northwestern University
• Kerri Wingert, Field Test Unit Co-Lead and Coherence Reviewer, Good
• Question Research & Evaluation, LLC
• Dan Voss, Writer, Northwestern University
• Sue Gasper, Writer for Revisions, University of Illinois Extension
• Jacob Noll, Writer for Revisions, Niles North High School (IL)
• Rachel Patton, Writer for Revisions, Rachel Patton Education Consulting
• Arlene Friend, Writer for Field Test, Denver Public Schools
• Meghan McCleary, Storyline Development, University of Illinois Extension
• Ann Rivet, Advisor on ESS Integration, Teachers College Columbia University

• Madison Hammer, Production Manager, University of Colorado Boulder
• Erin Howe, Project Manager, University of Colorado Boulder
• Stephanie Roberts, Copy Editor, Beehive Editing
• Gen Zoufal, Project Administrator, Northwestern University