Performance expectationApply scientific principles and evidence to explain how the rate of a physical or chemical change is affected when conditions are varied.
Explanations should be based on three variables in collision theory: number of collisions per unit time, particle orientation on collision, and energy required to produce the change. Conditions that affect these three variables include temperature, pressure, nature of reactants, concentrations of reactants, mixing, particle size, surface area, and addition of a catalyst.
Assessment is limited to simple reactions in which there are only two reactants and to specifying the change in only one condition at a time.
Every item written to HS-PS1-5 has to assess all three dimensions together, not the content alone. This is the structural change that made older practice material stop matching the exam.
Constructing Explanations and Designing Solutions
What a student at each level can do with HS-PS1-5. These drive how a cluster spreads difficulty across its items.
Summarised by ScienceIQ from the NYSED Performance Level Descriptions for Physical Science: Chemistry. These are our wording, not the Department’s — the official descriptions are the authority.
Identify evidence for how rate changes when conditions vary.
Predict or describe how rate changes when conditions vary.
Use evidence to predict and explain how varied conditions affect rate.
Apply scientific principles and evidence to explain how varied conditions affect rate.
Phenomenon stimulus, connected items across the required types, answer key, rubric and figures drawn deterministically from a structured spec — in the format your students will sit.