Pre-Lab Quiz: Determination of Density
A block has a mass of 4.465 g and a volume of 132.8 cm3. Calculate the density in g/cm3.
0.033622
A 2.83 g piece of zinc (density = 7.14 g/mL) is added to a graduated cylinder that contains 12.13 mL H2O. . What will be the final volume reading on the graduated cylinder, in mL?
12.53
Calculate the volume of a box, in cubic centimeters, which is 423 cm long, 12 cm wide, and 25 cm high. Report your answer with correct significant figures in cubic centimeters.
130000
What is the correct way to report the length of the rectangle in centimeters?
15.60 cm
A graduated cylinder contains 10.00 mL water. A 14.74 g piece of aluminum is added to the water, and the volume rises to 15.46 mL. What is the density of the aluminum in g/mL?
2.7
A 24.5 g sample of solution has a density of 0.768 g/mL. What is the sample volume (in mL)?
31.9
A series of measurements in the lab led to an experimental result of 32.9 mL, with a calculated standard deviation of 0.3 mL. What is the standard way to report this result?
32.9 ± 0.3 mL
What is the correct reading for the graduated cylinder in the close-up?
40.5 mL
What are the best practices while sharing a lab balance with other students?
Brush off any chemical dust around the balance after each use. Alert your TA or instructor about any issues with the balance.
The equation to calculate density is _____ , where D is the density, m is the _______ , and V is the ________
D=m/v mass volume
Which of the following properties is an extensive property?
Mass
Suppose that two students perform a gas law experiment multiple times, resulting in the average PV products reported here. Student A: 1.19 x 106 ± 350000 Pa-mL Student B: 1.2 x 106 ± 22000 Pa-mL The more precise work was done by _________ because _____________.
Student B that student's data has a smaller standard deviation
In order to use a pipet, place a ______ at the top of the pipet. Use this object to fill the pipet such that the __________of the liquid is even with the volume line. Release the liquid, touching the tip of the pipet to the side of the container if necessary to release the last drop ___________ the pipet tip.
bulb or pump meniscus outside
When a vinegar and oil salad dressing separates into two layers, the oil floats on top of the vinegar. The density of the oil ______ the density of the vinegar.
is less than
When using the Tare function on a balance, start by _______. Then, ___________ to cancel out that mass. Finally, __________and record the mass of your sample.
placing the glassware on the balance press the Tare/Zero button add your sample to the glassware
