Question 1

Which of the following devices provides the most accurate and precise measurement of a specific volume of liquid in the laboratory?

Accepted Answer

Volumetric pipet

Question 2

A student dispenses 10.029 g of water at 22°C using a volumetric pipet. If the density of water at 22°C is $$0.99780 \ \mathrm{g/mL}$$, what is the volume of water delivered by the pipet? (Use the correct number of significant figures.)

Accepted Answer

$$10.05 \ \mathrm{mL}$$

Question 3

When reading the volume of a liquid in a graduated cylinder, you should:

Accepted Answer

Read the value at the bottom of the meniscus

Question 4

A metal cylinder has a mass of $$51.8475 \ \mathrm{g}$$, is $$4.90 \ \mathrm{cm}$$ long, and has a diameter of $$1.2 \ \mathrm{cm}. $$What is the density of the cylinder? (Use $$\pi = 3.14$$ and round to the correct number of significant figures.)

Accepted Answer

$$9 \ \mathrm{g/cm^3$}$$

Question 5

Which of the following statements about laboratory balances is TRUE?

Accepted Answer

They must be calibrated each time before use to ensure accuracy.

Question 6

A student measures the mass of a metal bolt as $$10.8148 \ \mathrm{g}. $$When the bolt is placed in a graduated cylinder containing $$20 \ \mathrm{mL} of $$water, the water level rises to $$21 \ \mathrm{mL}. $$What is the density of the bolt? (Use the correct number of significant figures.)

Accepted Answer

$$10 \ \mathrm{g/cm^3$}$$

Question 7

Why is it important to use the density of water at the correct temperature when calibrating a volumetric pipet?

Accepted Answer

Because the density of water varies with temperature, affecting volume calculations

Question 8

Which of the following is a major source of error when using a beaker to measure liquid volume?

Accepted Answer

Beakers are not calibrated for precise volume measurements

Question 9

A student needs to measure $$25.00 \ \mathrm{mL} of a $$solution as accurately as possible. Which device should they use?

Accepted Answer

Volumetric pipet

Question 10

If a graduated cylinder is used to measure the volume of an irregularly shaped object by water displacement, which of the following best describes the process?

Accepted Answer

Subtract the initial water volume from the final water volume after the object is added

Question 11

Which of the following best explains why the meniscus forms in a graduated cylinder?

Accepted Answer

It is caused by the interaction between the liquid molecules and the wall of the cylinder

Question 12

A student records the mass of a sample as $$12.3456 \ \mathrm{g}$$ using an analytical balance. How many significant figures should be reported?

Accepted Answer

6

Question 13

Which of the following is the correct formula for calculating the volume of a cylinder?

Accepted Answer

$$V = \pi r^2$ h$$

Question 14

A student uses a graduated cylinder to measure $$20 \ \mathrm{mL} of $$water, but the true volume is $$19.8 \ \mathrm{mL}. $$What type of error is this most likely an example of?

Accepted Answer

Systematic error

Question 15

Which of the following best describes the difference between accuracy and precision?

Accepted Answer

Accuracy is how close a measurement is to the true value; precision is how reproducible measurements are

Question 16

A student measures the mass of a sample three times and gets values of $$10.01 \ \mathrm{g}$$, $$10.02 \ \mathrm{g}$$, and $$10.00 \ \mathrm{g}. $$The true mass is $$9.80 \ \mathrm{g}. $$Which statement is correct?

Accepted Answer

The measurements are precise but not accurate

Question 17

Which of the following is NOT a recommended practice when using an analytical balance?

Accepted Answer

Weighing hot objects

Question 18

A student needs to determine the density of a solution. Which measurements are required?

Accepted Answer

Mass and volume of the solution

Question 19

Why is it important to use significant figures when reporting measurements in chemistry?

Accepted Answer

They reflect the precision of the measuring instrument

Question 20

A student uses a beaker to measure $$50 \ \mathrm{mL} of $$water, but the actual volume is $$47 \ \mathrm{mL}. $$What is the percent error?

Accepted Answer

$$6.4\%$$

Measurement of Mass, Volume, and Density in General Chemistry

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