Evidence boundary
Use supplied spectra, reference tables, and approved simulations only.
Explicit science instruction
Spectroscopic identification is strongest when several measured lines agree with a reference pattern. One visually similar color is weak evidence.
Choose a numerical tolerance before comparing lines and apply it consistently. Document unmatched lines rather than hiding them.
Calibration and spectral resolution limit certainty, so conclusions should report both the match and the tolerance used.
Vocabulary: reference spectrum; calibration; spectral resolution; tolerance; pattern match.
Worked example with reasoning
Unknown lines are 411, 435, 487, and 655 nm. A reference lists 410, 434, 486, and 656 nm. Every difference is 1 nm or less, so the unknown strongly matches that reference under a ±2 nm rule.
Guided question
Compare an unknown line set with two fictional references and justify a tolerance before choosing the stronger match.
Independent work
- Create a reference/unknown difference table.
- Apply one stated tolerance consistently.
- Report the best-supported match and any unmatched feature.
- Propose one calibration check that would improve confidence.
Investigation / Data Lab
Preserve the raw line positions, difference calculations, tolerance rule, final match, uncertainty, and one revision.
Misconception check
Matching one line is not enough for strong identification; multiple independent matches provide stronger evidence.
Formative understanding check
Why is a multi-line pattern stronger evidence than one matching wavelength?
Reveal response
Multiple matches constrain the source more strongly and reduce the chance of coincidental agreement.
Mentor evidence conference
Ask Archaemenes to challenge your tolerance choice and whether it was applied consistently.
Teacher guidance
Foundation: Match lines using a supplied tolerance.
Core: Build a difference table and justify an identification.
Extended: Analyze how a systematic calibration offset would change the conclusion.
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