Q: A student measures the mass of a sample as 68.60 g and its volume as 9.5 mL. What is the density of the sample, rounded to the correct number of significant figures?

$$\frac{68.60\ \text{g}}{9.5\ \text{mL}} = 7.2\ \text{g/mL}$$

Q: Which of the following is the correct conversion factor for converting meters to centimeters, as shown in $$image_7$$?

$$\frac{100\ \text{cm}}{1\ \text{m}}$$

Q: A student needs to convert 2.5 hours to minutes. Which conversion factor should they use, as shown in $$image_6$$?

$$\frac{60\ \text{min}}{1\ \text{h}}$$

Q: Which of the following is the correct equality for converting kilograms to pounds, as shown in $$image_10$$?

$$1\ \text{kg} = 2.20\ \text{lb}$$

Question 1

Which of the following statements about significant figures is correct according to the rules shown in the study materials and $$image_1$$?

Accepted Answer

Zeros between nonzero numbers are always significant.

Question 2

A student measures the mass of a sample as 68.60 g and its volume as 9.5 mL. What is the density of the sample, rounded to the correct number of significant figures?

Accepted Answer

$$\frac{68.60\ 	ext{g}}{9.5\ 	ext{mL}} = 7.2\ 	ext{g/mL}$$

Question 3

Which of the following is an example of an exact number, as defined in the study materials and $$image_2$$?

Accepted Answer

The number of capsules in a bottle labeled '5 capsules'

Question 4

A measurement is recorded as 43.00. According to the rules for significant figures, how many significant figures does this number have?

Accepted Answer

4

Question 5

Which metric prefix represents a factor of $$10^{-6}$$, as shown in $$image_5$$?

Accepted Answer

micro

Question 6

If a person weighs 178 lb, what is their mass in kilograms, using the conversion factor $$1\ 	ext{kg} = 2.20\ 	ext{lb}$$ and rounding to the correct number of significant figures?

Accepted Answer

$$80.9\ 	ext{kg}$$

Question 7

Which of the following is a physical change, according to the examples in $$image_14$$ and Table 3.3?

Accepted Answer

Water boils to form water vapor.

Question 8

Which of the following is a chemical change, according to the examples in Table 3.3?

Accepted Answer

A piece of wood burns and produces heat, ashes, carbon dioxide, and water vapor.

Question 9

Which of the following statements about the arrangement of particles in solids, liquids, and gases is correct, based on Table 3.1?

Accepted Answer

Particles in a liquid are random and close.

Question 10

Which of the following is the correct scientific notation for 0.00086, according to the rules in the study materials?

Accepted Answer

$$8.6 	imes 10$$^{-4}$$

Question 11

Which of the following is the correct conversion factor for converting meters to centimeters, as shown in $$image_7$$?

Accepted Answer

$$\frac{100\ 	ext{cm}}{1\ 	ext{m}}$$

Question 12

A student needs to convert 2.5 hours to minutes. Which conversion factor should they use, as shown in $$image_6$$?

Accepted Answer

$$\frac{60\ 	ext{min}}{1\ 	ext{h}}$$

Question 13

Which of the following is the correct equality for converting kilograms to pounds, as shown in $$image_10$$?

Accepted Answer

$$1\ 	ext{kg} = 2.20\ 	ext{lb}$$

Question 14

Which of the following substances will float in water, based on the density values in $$image_13$$?

Accepted Answer

Ice

Question 15

Which of the following is the correct step-by-step approach to solving a conversion factor problem, as shown in $$image_9$$?

Accepted Answer

State the given and needed quantities, write a plan, state equalities and conversion factors, set up the problem to cancel units and calculate the answer.

Chemistry and Measurements: Units, Significant Figures, and Problem Solving

Guida di studio - Domande di pratica

Study guide - Flashcard