Q: A concrete block measures 7.36 cm long, 5.23 cm wide, and 1.2 cm thick. What is its volume in cubic centimeters, and how many significant figures should the answer have?

$$7.36 \times 5.23 \times 1.2 = 46\ \mathrm{cm^3$}$$, 2 significant figures

Question 1

Which of the following best describes the image labeled 'Oxygen' shown above?

Accepted Answer

A molecule consisting of two oxygen atoms bonded together, representing an element.

Question 2

Which statement best explains why the zeroes in the numbers 0.0032 and 0.00006 (as shown in the image above) are not considered significant?

Accepted Answer

They are leading zeroes, which are never significant.

Question 3

Which of the following is an example of a physical property?

Accepted Answer

Density

Question 4

A student measures the mass of a sample as 12.30 g and its volume as 4.0 mL. What is the density of the sample, and how many significant figures should the answer have?

Accepted Answer

$$\frac{12.30\ \mathrm{g}}{4.0\ \mathrm{mL}} = 3.1\ \mathrm{g/mL}$$, 2 significant figures

Question 5

Which separation technique would be most appropriate to separate a mixture of sand and water?

Accepted Answer

Decanting

Question 6

Which of the following statements about scientific laws and theories is correct?

Accepted Answer

A scientific law predicts future observations, while a theory explains why nature behaves as it does.

Question 7

Convert 120.0 $$^\circF to $$Kelvin using the appropriate formulas.

Accepted Answer

$$T_K = \frac{5}{9}(120.0 - 32) + 273.15 = 322.04\ \mathrm{K}$$

Question 8

Which of the following is an example of an intensive property?

Accepted Answer

Density

Question 9

A sample of gold has a mass of 96.5 g and a volume of 5.00 cm$$^3. $$What is its density?

Accepted Answer

$$19.3\ \mathrm{g/cm^3$}$$

Question 10

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture that appears to be one substance with uniform composition throughout.

Question 11

Which of the following is an example of a chemical change?

Accepted Answer

Rusting of iron

Question 12

A concrete block measures 7.36 cm long, 5.23 cm wide, and 1.2 cm thick. What is its volume in cubic centimeters, and how many significant figures should the answer have?

Accepted Answer

$$7.36 	imes 5.23 	imes 1.2 = 46\ \mathrm{cm^3$}$$, 2 significant figures

Question 13

Which of the following is a correct statement about energy changes in chemical reactions?

Accepted Answer

Energy is conserved; it is neither created nor destroyed.

Question 14

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom

Question 15

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

Accepted Answer

Accuracy refers to how close measurements are to the true value; precision refers to how close measurements are to each other.

Question 16

A marathon is 26.2 miles long. How many inches is this distance? (1 mile = 5,280 feet, 1 foot = 12 inches)

Accepted Answer

$$26.2 	imes 5280 	imes 12 = 1,658,496\ \mathrm{inches}$$

Question 17

Which of the following is a derived unit in the SI system?

Accepted Answer

Cubic meter ($$\mathrm{m^3$})$$

Question 18

Which of the following is a correct conversion factor for converting centimeters to meters?

Accepted Answer

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

Question 19

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements in fixed, definite proportions.

Chapter 1: Matter, Measurement, and Problem Solving – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard