Chang 1

Question 1

is the study of matter and the changes it undergoes.

Answer 1

Chemistry

Question 2

Three major advances in the past century have enabled us to prevent and treat diseases.

Answer 2

Health and Medicine

Question 3

is the basic unit of inheritance.

Answer 3

A gene

Question 4

is the basic unit of inheritance.

Answer 4

A gene

Question 5

is a by-product of many chemical processes

Answer 5

Energy

Question 6

major sources of energy are

Answer 6

fossil fuels (coal, petroleum, and natural gas

Question 7

Earth’s surface receives about _______ as much energy from sunlight as is contained in all of the known reserves of coal, oil, natural gas, and uranium combined.

Answer 7

10 times

Question 8

conversion of sunlight directly to electricity using devices is called

Answer 8

photovoltaic cells

Question 9

Another potential source of energy is,

Answer 9

nuclear fission

Question 10

_____ the process that occurs in the sun and other stars, generates huge amounts of energy without producing much dangerous radioactive waste.

Answer 10

Nuclear fusion

Question 11

A major disadvantage of burning fossil fuels is that they give off carbon dioxide, which is a

Answer 11

greenhouse gas

Question 12

The “engine” that drives the ongoing computer revolution is the

Answer 12

microprocessor

Question 13

The “engine” that drives the ongoing computer revolution is the

Answer 13

microprocessor

Question 14

the microprocessor

Answer 14

the tiny silicon chip that has inspired countless inventions, such as laptop computers and fax machines.

Question 15

the microprocessor

Answer 15

the tiny silicon chip that has inspired countless inventions, such as laptop computers and fax machines.

Question 16

All sciences, including the social sciences, employ variations of what is called the ________, a systematic approach to research.

Answer 16

sci- entific method

Question 17

Three major advances in this century have enabled us to
prevent and treat diseases:

Answer 17

1. Surgery with anesthesia
2. Enabling physicians to cure potentially fatal
   conditions, such as an inflamed appendix;
3. and the introduction of vaccines and antibiotics
   that make it possible to prevent diseases spread by
   microbes.

Question 18

fourth revolution in medicine.

Answer 18

Gene therapy

Question 19

carried by inborn damage to a single gene.

Answer 19

Cystic fibrosis and hemophilia

Question 20

is a by-product of many chemical processes.

Answer 20

Energy

Question 21

Major sources of energy are fossil fuels (coal, petroleum, and
natural gas) and the estimated reserve of these fuels will last
us another

Answer 21

50 – 100 years.

Question 22

______ viable source of energy for the future; 10
times as much energy from sunlight.

Answer 22

Solar energy

Question 23

the conversion of sunlight
directly to electricity using these devices.

Answer 23

Photovoltaic cells

Question 24

to use sunlight to obtain hydrogen
from water; the hydrogen can then be fed into a _______ to generate electricity.

Answer 24

fuel cell

Question 25

another potential source of energy.

Answer 25

Nuclear fission

Question 26

the process that occurs in the sun and other stars, generates huge amounts of energy without producing much dangerous radioactive waste.

Answer 26

Nuclear fusion

Question 27

are materials that have no electrical resistance and can therefore conduct electricity with no energy loss; at very low temperatures (more than 400 degrees Fahrenheit below the freezing point of water)

Answer 27

Superconductors

Question 28

the “engine” that drives the ongoing computer revolution

Answer 28

Microprocessor

Question 29

The function of microprocessor is judged by the _____ with which it carries out mathematical operations such as addition.

Answer 29

speed

Question 30

Microprocessors have doubled speed in every

Answer 30

18 months.

Question 31

The quality of any microprocessor depends on the

Answer 31

purity of the silicon chip and ability to add the desired amount if other substances.

Question 32

replacing silicon with molecules; respond to light rather than to electrons

Answer 32

Molecular computing

Question 33

Optical computers also would have much greater storage capacity

Answer 33

than electronic computers.

Question 34

insects communicate with one another by emitting and reacting to special molecules _____

Answer 34

Pheromones

Question 35

a tentative explanation for a set of observations

Answer 35

Hypothesis

Question 36

a concise verbal or mathematical statement of a relationship between phenomena that is always the same under the same conditions.

Answer 36

Law

Question 37

a unifying principle that explains a body of facts and/or those laws that are based on them.

Answer 37

Theory

Question 38

Democritus

Answer 38

Atomic Theory

Question 39

has a definite (constant) composition and distinct properties.

Answer 39

Substance

Question 40

has a definite (constant) composition and distinct properties.

Answer 40

Substance

Question 41

a combination of two or more substances in which the substances retain their distinct identities

Answer 41

Mixture

Question 42

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

Answer 42

Element

Question 43

112 elements have been positively identified;______ occur naturally on Earth and the rest have been created via _____ processes.

Answer 43

83, nuclear

Question 44

depends on how much matter is being considered (mass, length, volume)

Answer 44

Extensive property

Question 45

does not depend on how much matter is being considered (density, temperature) does not depend on how much matter is being considered (density, temperature)

Answer 45

Intensive property

Question 46

can be determined directly while microscopic on the atomic or molecular scale must be determined by an indirect method

Answer 46

Macroscopic properties

Question 47

is the lowest temperature that can be attained theoretically.

Answer 47

0 Kelvin

Question 48

tells us how close a measurement is to the true value of the quantity that was measured.

Answer 48

Accuracy

Question 49

refers to how closely two or more measurements of the same quantity agree with one another.

Answer 49

Precision

Question 50

It is important to indicate the margin of error in a measurement by clearly indicating the

Answer 50

number of significant figures

Question 51

are the meaningful digits in a measured or calculated quantity.

Answer 51

significant figures

Question 52

hypothesized that our universe burst into being billions of years ago in a gigantic explosion, or Big Bang.

Answer 52

George Gamow

Question 53

The universe was born about

Answer 53

15 billion years ago.

Question 54

1. First, measurements showed that the universe is expanding; that is, galaxies are all moving away from one another at high speeds

Answer 54

Gamow’s Hypothesis:

Question 55

The detection of cosmic background radiation; searingly hot universe and has cooled down to a mere 3K (-270 degrees C); at this temp, most energy is in the microwave region.

Answer 55

Gamow’s Hypothesis:

Question 56

The detection of ______; searingly hot universe and has cooled down to a mere 3K (-270 degrees C); at this temp, most energy is in the microwave region.

Answer 56

cosmic background radiation

Question 57

Gamow’s Hypothesis:

Answer 57

The discovery of primordial helium

Question 58

a strong source of light and radio signals that is thought to be an exploding galaxy at the edge of the universe; 10 billion light years away (a light year is the distance traveled by light in a year)

Answer 58

Quasar

Question 59

is the distance traveled by light in a year

Answer 59

a light year

Question 60

A hydrogen atom has only one electron which is stripped by the light from a quasar in a process known as

Answer 60

ionization

Question 61

all matters consists of very small, indivisible particles (atomos – uncuttable or indivisible); not accepted by Plato and Aristotle

Answer 61

Democritus

Question 62

all atoms of a given element are identical, same size, mass and chemical properties; compounds are composed of atoms of more than one element; a chemical reaction only involves separation, combination, or rearrangement of atoms.

Answer 62

Dalton

Question 63

states that different samples of the same compound always contain its constituent elements in the same proportion by mass.

Answer 63

Law of Definite Proportions (Joseph Proust)

Question 64

if two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in ratios if small whole numbers.

Answer 64

Law of Multiple Proportions (John Dalton)

Question 65

matter can be neither created nor destroyed.

Answer 65

Law of Conservation of Mass (John Dalton)

Question 66

is the basic unit of an element that can enter into chemical combination.

Answer 66

Atom

Question 67

the emission and transmission of energy through space in the form of waves.

Answer 67

Radiation

Question 68

negatively charged plate

Answer 68

Cathode

Question 69

positively charged plate;

Answer 69

anode

Question 70

when the ray strikes the special coated surface, it produces a

Answer 70

strong fluorescence or bright light

Question 71

to determine the ratio of electric charge to the mass of an individual electron. (−1.76𝑥108𝐶/𝑔)

Answer 71

Cathode ray tube (J. J Thompson)

Question 72

found the charge of an electron to be −1.60𝑥10−19𝐶

Answer 72

Robert Millikan

Question 73

X-rays (noticed that cathode rays caused glass and metals to emit very unusual rays)

Answer 73

Wilhelm Rontgen

Question 74

he found that exposing thickly wrapped photographic plates to a certain uranium compound caused them to darken, even without the stimulation of cathode rays.

Answer 74

Antoine Becquerel

Question 75

suggested the name “radioactivity” to describe this spontaneous emission of particles and/or radiation.

Answer 75

Marie Curie

Question 76

consists of positively charged

Answer 76

Alpha rays

Question 77

are electrons and deflected by the negatively charged plate

Answer 77

Beta rays

Question 78

no charge and are not affected by an external field

Answer 78

Gamma rays

Question 79

atoms that have the same atomic number but different mass numbers

Answer 79

Isotopes

Question 80

isotopes of same element have same characteristics forming the same types of compounds and displaying similar

Answer 80

reactivities.

Question 81

an isotope contains one proton and one neutron, and tritium has one proton and two neu

Answer 81

deuterium

Question 82

is a good conductor of heat and electricity.

Answer 82

Metal

Question 83

is usually a poor conductor of metalloids

Answer 83

non- metal

Question 84

have properties that are intermediate between those of metals and non-metals

Answer 84

metalloids

Question 85

is an aggregate of at least two atoms in a definite arrangement held together by chemical forces (also called chemical bonds).

Answer 85

molecule

Question 86

Two standard types of molecular models are currently in use:

Answer 86

ball-and-stick models and space-filling models

Question 87

balls are same size and represented by a specific color

Answer 87

ball-and-stick models

Question 88

represented by truncated balls held together by snap fasteners.

Answer 88

space-filling models

Question 89

is a charged species formed from a neutral atom or molecule when electrons are gained or lost as the result of a chemical change.

Answer 89

Ion

Question 90

is a charged species formed from a neutral atom or molecule when electrons are gained or lost as the result of a chemical change.

Answer 90

Ion

Question 91

formed from cations and anions.

Answer 91

Ionic compound

Question 92

is one of two or more distinct forms of an element. (𝑂2, 𝑂3)

Answer 92

Allotrope

Question 93

Two allotropic forms of the element carbon

Answer 93

diamond and graphite

Question 94

dramatically different not only in properties but in their relative cost.

Answer 94

diamond and graphite

Question 95

a substance used as an an anti-septic and as a bleaching agent for textiles and hair.

Answer 95

Hydrogen peroxide –

Question 96

tells us which elements are present and the simplest whole-number ratio of their atoms, but not necessarily the actual number of atoms in a given molecule.

Answer 96

Empirical formula

Question 97

are the true formulas of molecules.

Answer 97

Molecular formula

Question 98

The formulas of ionic compounds are________ their empirical formulas because ionic compounds do not consist of discrete molecular units.

Answer 98

always the same as

Question 99

contain carbon, usually in combination with elements such as hydrogen, oxygen, nitrogen, and sulfur

Answer 99

Organic compounds

Question 100

All other compounds are classified as inorganic compounds.

Answer 100

true

Question 101

All other compounds are classified as inorganic compounds.

Answer 101

true