Final answer:
The word 'observant' means being alert and perceptive. Observation is crucial for scientific investigation.
Explanation:
The word observant means being alert and perceptive in noticing things. In the context provided, it refers to the class being surprised by the chemical reaction.
Being observant is a key quality for scientists as they need to carefully observe phenomena before drawing conclusions or making hypotheses.
Observation is the act of noting or detecting phenomena through the senses, crucial in the process of scientific investigation.
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