Q: Which of the following is a correct example of dimensional analysis for converting 24 kilometers per minute to meters per second?

$$24\ \text{km/min} \times \frac{1000\ \text{m}}{1\ \text{km}} \times \frac{1\ \text{min}}{60\ \text{s}}$$

Q: A solution is prepared by mixing 10.89 mL of a liquid with a density of 2.1 g/mL. What is the mass of the liquid, rounded to the correct number of significant figures?

$$10.89 \times 2.1 = 22.869 g$$, rounded to 2 sig figs: 23$ g

Question 1

A student measures the boiling point of water as 98.5 $$^\circC$$, 101.2 $$^\circC$$, and 100.0 $$^\circC. $$The accepted value is 100.0 $$^\circC. $$Which statement best describes the student's measurements?

Accepted Answer

The measurements are neither accurate nor precise.

Question 2

Which piece of laboratory glassware is best for measuring exactly 25.00 mL of a solution for a titration?

Accepted Answer

Volumetric pipette

Question 3

A pharmacist dispenses 15.6 g of antibiotic capsules. If each capsule weighs 0.65 g, how many capsules were dispensed?

Accepted Answer

$$\frac{15.6}{0.65} = 24$$ capsules

Question 4

Which of the following numbers has 4 significant figures?

Accepted Answer

98.60

Question 5

Convert 4,072,000 to scientific notation with the correct number of significant figures.

Accepted Answer

$$4.072 	imes 10^6$

Question 6

A sample has a mass of 35.2 g and a density of 1.60 g/mL. What is its volume?

Accepted Answer

$$\frac{35.2}{1.60} = 22.0 mL$$

Question 7

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

Accepted Answer

Precision is how close measurements are to each other; accuracy is how close measurements are to the accepted value.

Question 8

A lake has a surface area of $$100\ 	ext{mi}^2$$ and an average depth of 20 ft. If the mercury concentration is $$0.4\ \mu	ext{g}/	ext{L}$$, what is the total mass of mercury in kilograms in the lake? (1 mi$$^2$$ = $$2.59 	imes 10^6$ m^2$, 1 ft = 0.3048 m, 1 m^3$ = 1000 L)

Accepted Answer

About $$2.4 kg$$

Question 9

Which of the following is the correct scientific notation for 0.000081?

Accepted Answer

$$8.1 	imes 10$$^{-5}$$

Question 10

Which of the following best describes an isotope?

Accepted Answer

Atoms with the same number of protons but different numbers of neutrons.

Question 11

A student adds 13.1 cm, 1.2039 cm, and 15.77109 cm. What is the answer rounded to the correct number of significant figures?

Accepted Answer

30.0 cm

Question 12

Which of the following is a correct example of dimensional analysis for converting 24 kilometers per minute to meters per second?

Accepted Answer

$$24\ 	ext{km/min} 	imes \frac{1000\ 	ext{m}}{1\ 	ext{km}} 	imes \frac{1\ 	ext{min}}{60\ 	ext{s}}$$

Question 13

Which of the following statements about subatomic particles is correct?

Accepted Answer

Neutrons and protons have nearly the same mass.

Question 14

Which of the following is the correct number of protons, neutrons, and electrons for $$^{36}_{17}	ext{Cl}^-$$?

Accepted Answer

17 protons, 19 neutrons, 18 electrons

Question 15

Which of the following best describes the charge and location of an electron in an atom?

Accepted Answer

Negative charge, located outside the nucleus

Question 16

A solution is prepared by mixing 10.89 mL of a liquid with a density of 2.1 g/mL. What is the mass of the liquid, rounded to the correct number of significant figures?

Accepted Answer

$$10.89 	imes 2.1 = 22.869 g$$, rounded to 2 sig figs: 23$ g

Question 17

Which of the following is a correct statement about the periodic table?

Accepted Answer

Periods are horizontal rows and groups are vertical columns.

Question 18

Which of the following best describes the process of calibration in the laboratory?

Accepted Answer

Configuring an instrument to provide a result within an acceptable range.

Question 19

Which of the following is the correct value for Avogadro's number?

Accepted Answer

$$6.022 	imes 10$$^{23}$$

General Chemistry Fundamentals: Measurement, Atomic Structure, and the Periodic Table

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