Lab Safety
Can you eat or drink in the lab?
No
A ____ has a definite shape
Solid
What is the equation for density?
D=m/v
What is a hypothesis?
An educated guess
What is the equation for percent error?
% error=accepted value-experimental value /accepted value
If glass breaks in the lab, what should you do?
Tell the teacher
At what temperature does water boil?
100°C/212°F
What is the equation for volume
V=m/d
The Method of gathering information by using your senses is called a _____
Observation
An object has a mass of 35.0 grams. On Anthony’s balance, it weighs 34.85 grams. What is the percent error of his balance?
0.43%
Can you wear dangling jewelry in the lab?
No
Temperature where a solid turns into a liquid is what?
Melting point
What is the equation for mass?
M=DxV
What is a control in an experiment?
Anything that does not change
Lucas estimated the weight of his pet rabbit, Blu, to be 5.55 pounds. Blu’s actual weight is 4.75 pounds. Find the percent error.
15.8%
What kind of shoes do you wear in the lab?
Closed toed shoes
True/False
Mass is the measure of how much matter an object has
True
A cricket ball has a density of 0.8 g/cm3 and a mass of 165 grams. Find the volume of the cricket ball
V=206.25
Does the independent variable change in an experiment?
No.
A student measures that a piece of string is 2.6 cm, but the actual length of the string is 2.9 cm. What is the student's percent error?
10.3%
Why do you wear goggles in the lab?
To protect your eyes from harmful chemicals
Rusting is a _____ change
Chemical
A piece of carbon has a density of 2.2 g/cm3 and a volume of 70 cm3. Find the mass of the piece of carbon
M=154
Name the steps of the scientific method
Question, Research, Hypothesis, Experiment, Data Analysis, and Conclusion
A reaction between one mole of sodium and one mole of chloride should yield 42 grams of sodium chloride. In your experiment, the actual yield is 32.73 grams. Calculate the percent error of your experiment.
22.07%