Chapter 1

Question 1

how to calculate sig. figs. through multiplication and division

Answer 1

“how many sig. figs.?” *The result should have the same number of sig. figs. as the number with the least

Question 2

how to calculate sig. figs. through addition and subtraction

Answer 2

“which column is uncertain?” *Only one uncertain digit is kept

Question 3

Exact Numbers

Answer 3

• known by definition, not by measurement
  - e.g. 12 inches=1 foot
• have an infinite number of sig. figs.

Question 4

Matter

Answer 4

anything that has mass and occupies space

Question 5

Macroscopic Level Chemical Reactions

Answer 5

reactions and the results that are visible to the human eye. e.g. fire, rust, alka-seltzer dissolving

Question 6

Scientific Law

Answer 6

a concise verbal or mathematical statement of a reliable relationship between phenomena

Question 7

Scientific Hypothesis

Answer 7

a tentative explanation for any observations

Question 8

Scientific Theory

Answer 8

a unifying principle that explains a body of experimental observations and the laws that are based on them

Question 9

Substance

Answer 9

a form of matter that has a definite (CONSTANT) composition and distinct properties. can be either elements or compounds

Question 10

Mixture

Answer 10

a combination of two or more substances in which the substances retain their distinct identities (do not have a universal constant composition)

Question 11

Homogeneous Mixture

Answer 11

a mixture where the composition of the mixture is uniform throughout

Question 12

Heterogeneous Mixture

Answer 12

the composition is not uniform

Question 13

States of Matter

Answer 13

solids, liquids, gases

Question 14

Elements

Answer 14

a substance that cannot be separated into simpler substances by chemical means

Question 15

Constituent Elements

Answer 15

the elements that make up a compound

Question 16

Physical Process

Answer 16

a process that does not change the identity of the matter. e.g. boiling, melting, freezing

Question 17

Quantitative Properties

Answer 17

properties that can be measured because they are expressed using numbers

Question 18

Weight

Answer 18

the force exerted by an object or sample due to gravity

Question 19

Mass

Answer 19

a measure of the amount of matter in an object or sample

Question 20

Kelvin

Answer 20

• known as the absolute zero scale, meaning that the lowest temperature possible is 0 K
• units of Celcius and Kelvin are equal in magnitude, so a degree Celcius is equivalent to a Kelvin

Question 21

Density

Answer 21

the ratio of mass to volume (mass/volume)

Question 22

Qualitative Properties

Answer 22

not requiring explicit measurement

Question 23

Physical Properties

Answer 23

properties that can be observed and measured without changing the identity of a substance

Question 24

Physical Change

Answer 24

one in which the state of matter changes but the identity of the matter does not change

Question 25

Chemical Properties

Answer 25

to observe these properties, we must carry out a chemical change.

Question 26

Chemical Change

Answer 26

after a chemical change, the original substance will no longer exist. What remains is a different substance. We cannot recover the original substance by means of a physical process

Question 27

Extensive Property

Answer 27

depends on the amount of matter. e.g. mass

Question 28

Intensive Property

Answer 28

does not depend on the amount of matter. e.g. density and temperature

Question 29

Uncertain Digit

Answer 29

the last digit in a measured number. The uncertainty associated with a measured number is generally considered to be plus/minus 1 in the place of the last digit

Question 30

Accuracy

Answer 30

tells us how close a measurement is to the true value

Question 31

Precision

Answer 31

tells us how close multiple measurements of the same thing are to one another

Question 32

Conversion Factor

Answer 32

a fraction in which the same quantity is expressed one way in the numerator and another way in the denominator

Question 33

Dimensional Analysis

Answer 33

the use of conversion factors in problem solving. A.K.A. factor-label method