Following Spoken Instructions in a Lab
A teacher gives spoken instructions for a practical task: 'Right, everyone - before you touch anything, put your goggles on. Then take one beaker from the front bench, not two. Fill it to the 200 mL line with the clear solution, and add the blue powder one spoon at a time, stirring after each spoon. Stop when the colour stops changing. If it gets hot, tell me straight away and put the beaker down on the mat - don't hold it. You have fifteen minutes, and I'll come round to check before you write anything up.' A student, Amira, puts on her goggles, takes two beakers, fills one to 200 mL, and adds all the powder at once without stirring.
1. List the instructions Amira did not follow, in the order the teacher gave them, and explain why the order matters.
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Amira followed the first instruction (goggles on) but then broke three others:
- Quantity of beakers. The teacher said 'one beaker, not two'. Amira took two.
- Rate of adding powder. The teacher said 'one spoon at a time, stirring after each spoon'. Amira added all the powder at once without stirring.
- Stopping rule. The teacher said to stop 'when the colour stops changing'. Adding everything at once makes this rule impossible to apply, because she cannot observe the colour change step by step.
The order matters because the instructions are sequential and dependent. The stopping rule only works if powder is added gradually; adding it all at once destroys the very signal she was told to watch for. Similarly, the safety instruction about heat only makes sense while the beaker is being handled carefully. Following a procedure means respecting its sequence, not just its individual steps.
2. The teacher said 'I'll come round to check before you write anything up.' What does this tell Amira about what to do next, and what should she do about the heat warning?
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The teacher's closing sentence sets a condition on the next stage: Amira must not begin the written report until the teacher has checked her work. So even if she finishes the practical, she should wait, keep her equipment tidy, and not start writing.
The heat warning is a standing safety instruction: 'If it gets hot, tell me straight away and put the beaker down on the mat - don't hold it.' Because Amira added all the powder at once, a sudden hot reaction is more likely, which makes this instruction especially relevant. If the beaker becomes hot, she should place it on the mat immediately, not hold it, and tell the teacher at once rather than waiting for the check.
This question tests listening for conditional instructions: 'if' clauses create duties that apply whenever the condition occurs, not only at the end of the task.