Use combined spectra to identify structure
A organic structure seminar gives ester C=O absorption and fragment consistent with ethyl group. Identify the most consistent structure. Use the labelled diagram or spectrum before giving the answer. Enter the answer and choose the interpretation that matches the HL chemistry evidence.
Worked practice: chemistry evidence and answer
Use the chemical evidence first, then enter the result and interpretation that match it.
Write a full answer
Now write the response in full, in your own words — this is what the exam asks for. The AI marks it on the same moves you built above (focus, evidence, technique, judgement) and gives feedback on reasoning, evidence, and expression.