Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements chemically combined in definite proportions

Question 2

Which statement about the law of constant composition is correct?

Accepted Answer

The elemental composition of a compound is always the same, regardless of its origin

Question 3

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

Accepted Answer

Water freezing to form ice

Question 4

A student separates a mixture of sand and salt by adding water, stirring, and then filtering. Which property is being used to separate the mixture?

Accepted Answer

Solubility

Question 5

Which of the following is an extensive property?

Accepted Answer

Mass

Question 6

Which statement correctly distinguishes between a pure substance and a mixture?

Accepted Answer

A pure substance has fixed properties throughout, while a mixture can have properties that vary from sample to sample

Question 7

Which of the following is a chemical property?

Accepted Answer

Ability to react with acid

Question 8

A sample of gas is compressed from 2.0 L to 1.0 L at constant temperature. Which property of the gas changes as a result?

Accepted Answer

Its volume

Question 9

Which of the following best describes the difference between an atom and a molecule?

Accepted Answer

An atom is the smallest building block of matter, while a molecule is a combination of two or more atoms

Question 10

Which separation technique would be most appropriate for separating a solution of salt water into its components?

Accepted Answer

Distillation

Question 11

A mixture of nitrogen and oxygen gases is an example of which type of matter?

Accepted Answer

Homogeneous mixture

Question 12

Which of the following statements about states of matter is correct?

Accepted Answer

Gases have no fixed volume or shape and can be compressed

Question 13

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

Accepted Answer

Density

Question 14

Which process is a chemical change?

Accepted Answer

Burning of gasoline

Question 15

A compound is analyzed and found to contain 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What law does this illustrate?

Accepted Answer

Law of definite proportions

Question 16

Which of the following best describes kinetic energy?

Accepted Answer

Energy due to the motion of an object

Question 17

Which formula correctly expresses the kinetic energy of an object?

Accepted Answer

$$KE = \frac{1}{2}mv^2$

Question 18

A car traveling at 65 mph has more kinetic energy than a car traveling at 35 mph because:

Accepted Answer

Kinetic energy increases as velocity increases

Question 19

Which of the following is NOT a method for separating mixtures based on physical properties?

Accepted Answer

Electrolysis

Question 20

Which statement about the composition of mixtures is correct?

Accepted Answer

Mixtures can be separated into their components by physical means

The Study of Chemistry: Classification and Properties of Matter, and the Nature of Energy

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