Day 9 · Catch four attractive wrong claimsYear 11 Chemistry · T1 W1–2 · Day 9 lesson

Target: detect and correct isotope, ion, notation and evidence errors across new story labels. Prepare: Cards B/C/E/F and isotope/ion fork.

1. Launch · 2 min. Show “A plus sign means add a proton.” Ask learners to reserve judgement until they check the model rule.
2. Model · 4 min. Correct to “for a monoatomic 1+ ion of the same isotope, one electron has been lost.” Explicitly state that an actual process cannot be inferred from a printed symbol alone.
3. Guided reading · 5 min. Audit three more statements: “C-12 and C-13 are different elements,” “23 on sodium is its atomic number,” and “a material label proves purity.” Mark rule or evidence source for each repair.
4. Practice route · 7 min. Choose Day 9 route; produce four corrected claim/evidence/limit triples. Use a fictional bicycle-parts catalogue label as a story, not a product specification.
5. Audit · 4 min. Partner checks each correction against Z→identity, A−Z→n, and charge→e while watching for unsupported product inference.
6. Exit · 3 min. “What extra information is required to know neutron count from Z alone?” Key: A of a particular isotope.