HS-PS1-6
The standard
Refine the design of a chemical system by specifying a change in conditions that would produce increased amounts of products at equilibrium.
Next Generation Science Standards
What this standard means
Students need to use Le Chatelier’s Principle to improve a reaction system that has reached equilibrium. They should choose one change, such as adding a reactant, removing a product, changing pressure, or changing temperature, and explain why it would make more product form.
Mastery looks like a clear cause and effect link from the visible change to particle behavior. Students can say which side the equilibrium shifts toward and why. Common trouble spots are thinking the reaction “stops” at equilibrium, changing more than one variable at once, or explaining shifts with memorized rules but no molecular reasoning.
Ways to teach it
- Hands-on activity: Use cobalt chloride equilibrium tubes in hot and cold water, then have students explain the color shift using particle collisions.
- Discussion prompt: Ask, “If a factory removes ammonia as it forms, what happens next at the molecular level?”
- Quick assessment: Give four reaction setups and have students choose one condition change that increases product, with a one-sentence explanation.
- Real-world connection: Analyze the Haber process and identify why high pressure helps produce more ammonia.
Plan a lesson for HS-PS1-6
Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.
Related standards
- MS-LS1-7
Develop a model to describe how food is rearranged through chemical reactions forming new molecules that support growth and/or release energy as this matter mov...
- 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,...
- MS-PS1-6
Undertake a design project to construct, test, and modify a device that either releases or absorbs thermal energy by chemical processes.
- HS-PS1-5
Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on t...