Question

1. choose the best answer.

in the middle of a chemical experiment, the students leave to eat lunch and hang out. which rule is violated?
leaving an experiment unattended
being serious in the lab
eating and drinking in the lab
working alone in the lab

1. match the correct term to complete the sentence.

if some experimental data is accidentally deleted from the study, this leads to a(n) error.

1. match the correct term to complete the sentence.

if a chemical instrument is known to be faulty and fails, this leads to a(n) error.

Explanation:

1. When students leave a chemical experiment in the middle, they are leaving the experiment unattended. This is a major safety and procedural violation in a lab as unattended experiments can lead to various hazards like chemical spills (if reactions go wrong without supervision), equipment damage (if heating/cooling processes are interrupted without someone to manage), etc. Being serious in the lab is a more general attitude aspect (not directly violated here as the key act is leaving the experiment). Eating and drinking in the lab is about consuming items in the lab space (they left to eat outside, so this isn't the violation). Working alone in the lab is about the number of people present (the problem doesn't mention if they were alone or in a group before leaving, but the main issue is leaving the experiment).
2. If experimental data is accidentally deleted, it's a random error. Random errors are unpredictable and can occur due to accidental actions (like a wrong click deleting data, human - error in data handling that isn't systematic).
3. If a chemical instrument is known to be faulty and fails, it's a systematic error. Systematic errors occur due to a flaw in the measurement system (here, the faulty instrument which will consistently give incorrect results in a particular way until fixed).

Answer:

1. leaving an experiment unattended
2. random
3. systematic