First-order half-life
A first-order process in a materials-analysis workshop has \(k=0.12\,\text{min}^{-1}\). Calculate the half-life. Use the labelled diagram, graph, or data table before calculating. 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.