Lab Safety
What is safety equipment? Describe with examples.
Safety Equipment is equipment that is already in the lab that you can use in the case of an emergency. EX: fume hood, fire blanket, fire extinguisher, eye wash, safety shower.
What is a Beaker?
Beakers are used to heat, mix, and transfer liquids. They make inaccurate measurements.
What are the 3 types of chemical exposure?
1)Injestion: Process of taking a chemical and swallowing it.
2)Inhalation: Gas enters the lungs.
3)Absorption through skin: substances enter the body through the skin.
What is the controlled Variable?
The controlled variable is something that is kept the same throughout the experiment.
Are non-zero numbers significant?
Yes.
What is PPE? Describe using examples.
PPE (Personal Protective Equipment) is personal equipment that you wear to protect yourself. EX: Lab coat, Gloves, Goggles.
What is a pipette?
A pipette is used for reliable dispensing and transferring small amounts of liquid. There are 2 types:
Marked: Deliver with great accuracy.
Unmarked: Just for drops, inaccurate.
How can you prevent chemical exposure?
By wearing PPE and using safety equipment.
What is the Dependent Variable?
The Dependent variable is the variable that changes because of the independent variable. It is what is getting measured.
What are captive zeros?
Captive zeros are zeros between two non-zero numbers. They are always significant.
How long should you use the eye wash and safety shower for?
15-20 minutes
What is an Erlynmeyer flask?
Erlynmeyer flasks are used to store, heat, and swirl to mix liquids. They make inaccurate measurements and they have a narrow neck and flat bottom.
What is the meniscus?
The Meniscus is the curve at the top of the liquid caused by the attraction of water to the walls of the graduated cylinder.
What is the Independent Variable?
The Independent variable is what the scientist chooses to change. A controlled experiment occurs when there is only 1 independent variable.
Are Final Zeros significant?
Only if a decimal point is present.
What should you do if you get fire on your clothes or skin?
STOP, DROP, AND ROLL
What is a graduated cylinder?
Very accurate for measuring multiple volumes. It has a narrow, tall cylindrical shape, and is not as accurate as a volumetric flask.
What is accuracy?
Accuracy is how close your measurments are to a target. Measurments are considered accurate if they are less than 5% away from a target.
What is the control group?
The control group is used as a basis for comparison.
How do you add/subtract significant figures?
round your answer to the same number of decimal points as the measurement with the least amount of decimal places.
Where should solid waste, liquid waste, and broken glass be disposed?
Broken Glass: In the broken glass bin.
Liquid Waste: In the sink.
Solid Waste: In the trashcan.
What is a Volumetric flask?
Used to prepare solutions and make dilutions. Volumetric flasks only measure 1 volume, so they are the most accurate. They have a long, thin neck and flat bottom.
What is precision?
Precision is how close your measurements are to each other. Measurements are considered precise if they are less than 10% away from one another.
What is the experimental group?
The experimental group is the group getting tested.
How do you multiply/divide significant figures?
round the answer to the same number of significant figures as the measurement with the least amount of significant figures.