Stemscopes Exam Science Safety and Lab Skills 2 — Questions and Answers
Question 1: What is a control group in an experiment?
- The group that receives the experimental treatment
- The group that is not exposed to the independent variable (Correct answer)
- The group with the most subjects
- The group that is observed last
Correct answer: The group that is not exposed to the independent variable
The control group is not subjected to the independent variable and serves as a baseline for comparing the experimental results.
Question 2: How should broken glass be disposed of in a lab?
- Put it in the regular trash
- Leave it on the bench for the teacher
- Place it in a designated sharps or broken glass container (Correct answer)
- Sweep it under the lab bench
Correct answer: Place it in a designated sharps or broken glass container
Broken glass must be placed in a designated sharps or broken glass container to prevent injury to lab workers.
Question 3: What does the triple beam balance measure?
- Volume
- Temperature
- Mass (Correct answer)
- Density
Correct answer: Mass
A triple beam balance is a precision instrument used to measure the mass of an object in grams.
Question 4: Which of the following is an example of a qualitative observation?
- The solution is 25°C
- The mass is 5.2 grams
- The liquid turned blue (Correct answer)
- The volume is 10 mL
Correct answer: The liquid turned blue
A qualitative observation describes a characteristic without using numbers, such as color, texture, or smell.
Question 5: What is the purpose of repeating an experiment multiple times?
- To make the experiment take longer
- To increase reliability and reduce the effect of random errors (Correct answer)
- To confuse the results
- To use more materials
Correct answer: To increase reliability and reduce the effect of random errors
Repeating experiments increases the reliability of results by reducing the impact of random errors and anomalous data.
Question 6: Which symbol on a chemical container indicates a flammable substance?
- A skull and crossbones
- A flame symbol (Correct answer)
- An exclamation mark
- A circle with a line through it
Correct answer: A flame symbol
A flame symbol on a chemical container indicates the substance is flammable and must be kept away from heat sources.
Stemscopes Exam Science Safety and Lab Skills 2
What is a control group in an experiment?