Question 1

Which of the following best describes the difference between a scientific law and a scientific theory?

Accepted Answer

A law summarizes a series of related observations; a theory gives the underlying reasons for them.

Question 2

A student measures the mass of a cube as 11.2 g and its volume as 8.0 cm$$^3. $$What is the density of the cube?

Accepted Answer

$$D = \frac{11.2\ \mathrm{g}}{8.0\ \mathrm{cm}^3} = 1.4\ \mathrm{g/cm}^3$$

Question 3

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

Accepted Answer

Filtration

Question 4

Which of the following is a chemical change?

Accepted Answer

Rusting of iron

Question 5

A sample of copper is heated from room temperature to 95$$^\circC. $$What happens to its density?

Accepted Answer

The sample expands.

Question 6

Which of the following is an example of a homogeneous mixture?

Accepted Answer

Tea with sugar

Question 7

Which of the following is the correct SI unit for measuring temperature?

Accepted Answer

Kelvin (K)

Question 8

How many significant figures are in the measurement 0.00450?

Accepted Answer

3

Question 9

Which of the following best describes potential energy?

Accepted Answer

Energy associated with position or composition

Question 10

Convert 0.0587 L to mL.

Accepted Answer

58.7 mL

Question 11

Which of the following is a physical property?

Accepted Answer

Melting point

Question 12

A student adds 58.358 and 269.1. What is the answer with the correct number of significant figures?

Accepted Answer

327.5

Question 13

Which of the following diagrams best represents a pure substance?

Accepted Answer

Diagram (c)

Question 14

Which prefix multiplier represents $$10^{-6}$$?

Accepted Answer

micro

Question 15

A cube has sides of length 3.0 cm and a mass of 67.5 g. What is its density?

Accepted Answer

$$D = \frac{67.5\ \mathrm{g}}{27\ \mathrm{cm}^3} = 2.5\ \mathrm{g/cm}^3$$

Question 16

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom

Question 17

Which of the following best describes accuracy?

Accepted Answer

How close measurements are to the true value

Question 18

Which of the following is a heterogeneous mixture?

Accepted Answer

Wet sand

Question 19

Which of the following is the correct formula for converting Celsius to Kelvin?

Accepted Answer

$$K = ^\circ C + 273.15$$

Question 20

Which of the following is a physical change?

Accepted Answer

Sublimation of dry ice

Introduction to Chemistry: Matter and Measurements

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