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Flashcards in Chemistry Final Deck (141):
1

Atomic Number

Number of Protons

2

Mass Number

Protons + Neutrons, depends on which isotope you are talking about (mass number varies in each element)

3

Atomic Mass

Weighted average atomic mass of the isotopes

4

deuterium/tritium

Different isotopes of Hydrogen

5

Isotopic Notation

Atomic Number--at the bottom (protons), Mass Number--at top, P+N

6

Ions

Unequal numbers of protons and electrons, cations (+) anions (-)

7

Fission

a type of nuclear change in which a target nucleus is bombarded by a neutron. The unstable nucleus should have split up in fission products and a few neutrons

8

Energy-Nuclear Fission

Energy is given off in a nuclear fission reaction, E=mc^2 (c=speed of light, 3 X 10^8 m/s), matter is converted to energy (mass of product is less than mass than the original mass), deltaE=deltamc^2

9

What does a negative change in energy mean?

Heat is lost, so heat is given off

10

Chain reaction

refers to any reaction in which one of the products becomes a reactant and thus makes t possible for the reaction to become self-sustaining

11

Critical mass

the amount of fissionable fuel required to sustain a chain reaction

12

Fissionable Uranium

U-235

13

Control Rods

Neutron absorbers, controls rate of reaction. Rods are lowered as fuel rods are inserted to slow down, as more U-235 is used, the rods are raised to continue the heat that is given off. Can be positioned to absorb fewer or more neutrons, rate of reaction depends on the position of the control rods

14

Primary Coolant

a liquid that comes in direct contact with the fuel bundles and control rods and carries away the heat. The coolant many times has boric acid, the boron atoms absorb neutrons and thus control the rate of fission and the temperature. The solution slows neutrons, thus making it more effective in producing fission

15

Secondary Coolant

the water in the steam generators that don't come in contact with the reactor. Transfers heat from the primary coolant to drive the turbine

16

Radioactivity

spontaneous change in which unstable nuclei decay

17

Fission reactions

requires a neutron to break apart a relatively unstable nucleus into two nuclei (of abut the same size)

18

Who first discovered radioactivity?

Madame Curie

19

Alpha particle

penetrates the least (blocked by a sheet of paper), helium (4/2He), positively charged particle emitted from nucleus, 2 protons, 2 neutrons, and a 2+ charge

20

Beta particle

penetrates more (blocked by a book) electron (0/-1e-), a hih speed electron emitted from the nucleus, has a negative 1 charge, mass number stays the same, atomic numer increases by 1

21

Gamma particle

the most penetrating (blocked by lead), emitted from the nucleus and has no charge or mass, it is a high-energy, short-wavelength photon.

22

Beta particle -- where does the electron come from?

It comes from a neutron

23

What makes isotopes stable/less stable?

Has to do with ratio of protons:neutrons

24

Isotopes above band of stability?

Undergoes Beta emission

25

Isotopes below band of stability?

Undergoes Alpha emission, has too many protons not enough neutrons

26

Chernobyl

operator error, the cooling water was disrupted, messed up a test, the fuel rods got too hot/gave too much heat, the chemicals around the fuel rods got too hot and caught on fire

27

Fukushima

Nuclear waste on cooling site couldn't be kept cool, so waste pool leaked out

28

T/F: One of the biggest problems with Nuclear Power plants is the storage of the spent fuel cells

TRUE

29

Two ways to deposit High-Level Nuclear Radioactive Waste

Storage on/near surface (distributed or centralized) or geological repository (open or sealed)

30

Greatest single source of background radiation?

Radon

31

Largest source of background radiation: natural sources or human-made sources

Natural sources

32

What is a free radical?

A highly reactive chemical species with one or more unpaired electrons

33

What units are used to measure radiation?

Curie (Ci)-used to measure how much radiation that is coming out of a sample, Sievert (Sv)-unit that relates to the amount of radiation energy that is absorbed by tissue

34

U.S. average of total annual radiation dose?

3600 microSieverts/yr, so .0036 Sv

35

What is ionizing radiation?

It's a type of radiation that collides with matter in such a way as to eject electrons from bonds

36

The cumulative effect of daily smoking exposes you to more radioactive material a year

True

37

Alpha decay

does the most damage to the tissue but does the least penetrating power. Can be very bad if it is inside the body-inhaled, etc.

38

Beta decay

More penetrating power, but not cause as much damage. It can penetrate skin. Dose intermediate damage

39

Gamma decay

can penetrate skin, can cause tissue damage (can kill cancer cells), breaks bonds

40

Half-Life

the time required for the level of radioactivity to fall to one-half its value

41

How much remains after 1 1/2 life? 2 1/2 lives?

50%; 25%

42

In terms of carbon dating, do dead organisms exchange carbon with the atmosphere?

No

43

Breeder Reactors

Convert non-fissionable U-238 into fissionable Pu-239. Pu-239 could be used to build nuclear weapons, it coverts spent fuel rods into useful fuel, Pu-239 cannot easily penetrate human skin but can be easily inhaled

44

Which coolant in a nuclear power plant is the one most likely to contain boric acid?

Primary coolant

45

The fundamental difference between a nuclear power plant and a conventional power plant is

the source of heat

46

Which is the heaviest of the common radioactive particles?

alpha

47

Ecological Footprint

a means of estimating the amount of biologically productive space (land, water, and sea surface) necessary to support a particular standard of living or lifestyle. The footprint for the US is 9.7 hectares per person, where as the global average is 2.7 hectares per person. The carbon footprint is a term used to describe how much carbon in the form of carbon dioxide an individual or society produces based on lifestyle choices.

48

Cradle-to-cradle

a phrase that is juxtaposed to the phrase cradle-to-grave. Cradleto-grave is the approach to analyzing the life cycle of an item, starting with the raw materials from which it came and ending with its ultimate disposal someplace, presumably the Earth. Cradle-to-cradle refers to a regenerative approach to the use of things in which the end of the life cycle of one item dovetails with the beginning of the life cycle of another, so that everything is reused rather than disposed of as waste.

49

Sustainability

Meeting the needs of the present without
compromising the ability of future generations to meet their needs

50

Carbon-14 undergoes radioactive decay. This means that there is a change in

the number of protons and/or neutrons in the nucleus.

51

What best summarizes why a nuclear power
plant cannot explode like a nuclear bomb?

A critical mass of fissionable material is
never achieved.

52

A nuclear power plant cannot undergo a nuclear explosion because

the
235
U is too dilute to produce a runaway reaction

53

A breeder reactor converts

nonfissionable U-238 to fissionable Pu-
239.

54

Which would contribute most to your annual
radiation exposure?

smoking a pack and a half of cigarettes
per day

55

What is the maximum one-time dose of radiation one can receive without suffering any
detectable physiological effects?

25 rem (0.25 Sv)

56

If
you started with 100.0 g of carbon-14, how
much would remain after 4 half-lives?

6.25 g

57

The purpose of the control rods is to

absorb neutrons given off in the fission
reaction

58

In nature, one element can change to another
by the process of

radioactive decay

59

When
131
I emits a β particle, what nuclide is
produced?

131
Xe

60

A factor of 1.0×10^−6 corresponds to the prefix

micro

61

A factor of 1.0×10^−3 corresponds to the prefix

milli

62

A factor of 1.0×10^−9 corresponds to the prefix

nano

63

The prefix centi means

one hundredth

64

What is the primary component of an exhaled breath?

N2

65

The major component of our atmosphere is

nitrogen

66

Approximately what percentage of the
Earth’s crust is composed of oxygen?

50%

67

What is the most appropriate concentration unit used to express the concentration
of a pollutant that has a concentration of
0.00004%?

ppm

68

A sample of air is analyzed and found to contain 0.0002 g of particulate matter in 40 m3 of air. What is the concentration of particulate matter?

5.00 µg/m3

69

Sugar dissolved in water is

a homogeneous mixture.

70

What is one difference between a mixture and a compound?

A compound can only be separated into
its components by chemical means

71

A bar of deodorant soap is a/an

mixture

72

Steam coming from a pan of boiling water is

compound

73

A sample of copper is a/an

element

74

Carbon monoxide is dangerous (even lethal)
because it

displaces oxygen from the blood

75

Which substance is most dangerous to
breathe, owing to its lack of odor?

CO

76

Toxicity is

the effect of a substance on health.

77

In which layer of the atmosphere are hikers
when they stand on the summit of Mt. Everest?

troposphere

78

A pure substance composed of two or more elements chemically combined is

a compound

79

Mixtures are divided into two classes based on their appearance. What are these two classes?

heterogeneous or homogeneous

80

The smallest part of an element which can be recognized as that element is

an atom

81

Compounds formed between two nonmetals will have which bond?

covalent

82

A catalytic converter

completes the oxidation of CO and unburned hydrocarbons and reduces NOx to N2 and O2.

83

What is considered a secondary pollutant?

O3

84

Which approach would reduce ALL forms of
indoor air pollution?

increasing the indoor/oudoor air exchange

85

Methane is the common name for which formula?

CH4

86

Ammonia is the common name for which formula?

NH3

87

What is the formula of titanium(IV) oxide?

TiO2

88

Consider the bonds in iron(III) oxide. Are the
bonds more ionic or more covalent?

ionic

89

ionic bonds

The attractions between anions and cations
in a crystal are known as

90

Elements with similar chemical properties are arranged in the same

group/vertical column

91

nanometer

one billion of a meter (1E10^-9)

92

Electromagnetic Spectrum (from shortest wavelength to longest)

gamma, X-rays, UV, visible, IR, microwave, radio

93

Electromagnetic spectrum (from longest to shortest wavelength)

radio, microwave, IR, Visible, UV, X-Rays, Gamma rays

94

Wavelength (in nanometers) of visible

400-700 nm

95

Purple -- short or long?

short, 400 nm

96

Red -- short or long?

long, 700 nm

97

Red -->

IR-->Microwave-->Radio

98

<--Violet

UV, X-Rays, Gamma Rays

99

frequency (v) formula

speed of light (c) / wavelength (lambda) in meters

100

relationship between frequency and wavelength

inversely related

101

Energy (E) formula

(h*c) / wavelength (lambda) or h*v

102

speed of light

3 X 10^8 m*s^-1

103

Planck's Constant (h)

6.626 X 10^-34 Js

104

Energy's relationship to wavelength?

inversely proportional, as wavelength

105

Green, Red, Violet, Yellow. In order of increasing energy per photon

violet > green > yellow > red

106

What happens to UV-C?

absorbed in the upper atmosphere, both oxygen and ozone absorb light of these wavelengths

107

O2 --> UV photon

2 O, O2 + O--> O3

108

Easier to break: O2 or O3

O3

109

Chapman Cycle

the first set of natural steady-state

110

UV Index

<2 (low) to 11+ (high)

111

How is ozone formed? (Basic formula)

Energy + 3 O2

112

Formula for number of shared electrons?

Shared Electrons = Needed - Actual

113

Formula for formal Charge

FC = Valence - (# of electrons + 3 of bonds)

114

UV-B

280-320 nm, most UV-B is absorbed by O3 in the stratosphere

115

UV-A

320-400least damaging, reaches Earth's surface in greatest amount

116

Incomplete Octet

B - needs 6, Be - 4, H - 2

117

Dobson Units

amount of UV radiation reaching a detector at ground level is correlated to the amount of ozone in column

118

frequency unit

1/s, Hertz

119

c = ... (in terms of v and lambda)

v * lambda

120

when will molecular geometries be different?

When there are lone pairs on the central atom

121

3 electron regions

trigonal planar

122

4 electron regions

tetrahedral

123

5 electron regions

trigonal bipyramidal

124

6 electron regions

octahedral

125

unit for molar mass?

g/mol

126

1 mol =

Element's grams

127

Avogadro's

6.02E23

128

Using Avogadro's

6.02E23 atoms = 1 mol

129

Most carbon found where?

in deep oceans

130

By what could a 300 nm photon be absorbed?

O3 but not O2

131

A gasoline’s octane rating is

a measure of the gasoline’s resistance to
causing knocking in a vehicle’s engine

132

Cracking is

the breaking of larger molecules into
smaller ones.

133

A catalyst

increases the rate of a chemical reaction
but is not consumed in the process.

134

What two fuels from wood, octane, anthracite, methane, and garbage are the best as far as energy ouput per unit mass?

octane and methane

135

Approximately what percentage of electricity generated in the US is hydroelectric?

10%

136

Soft lignite (brown coal) is the lowest grade of coal. Its chemical composition, and hence its heat of combustion, is most similar to that of

wood

137

What is NOT a consideration when selecting
a substance to be used as a fuel?

It must burn inside an internal combustion engine

138

When coal burns

chemical energy is converted to heat energy

139

The separation of a mixture of compounds
into the individual components is called

fractionation

140

A compound that has replaced tetraethyllead
as an octane booster is

methyl tert-butyl ether

141

Petroleum (crude oil) is a complex mixture
of thousands of substances, the majority of
which are

hydrocarbons