Chemistry: Arrangements Of Electrons In Atoms

Front 1

Scientists realized that the Rutherford model did not explain:

Back 1

where the electrons were located in the space around the nucleus

Front 2

first the Bohr model and then the Quantum Mechanical Model evolved as scientists studied the __________ and ________ of light by matter

Back 2

absorption and emission

Front 3

taking in of light by matter

Back 3

absorption

Front 4

giving off of light by matter

Back 4

emission

Front 5

the studies showed that there is an intimate relationship between _____ and an atom's electrons

Back 5

light

Front 6

the studies also showed that light behaves as both _____ and _________

Back 6

waves and particles

Front 7

Rhythmic disturbances that carry energy through matter or space

Back 7

Wave

Front 8

waves in which the medium moves at right angles to the direction the wave travels

Back 8

Transverse Waves

Front 9

Transverse waves do not always need a ______ to carry energy

Back 9

medium

Front 10

any material through which a wave can transfer energy

Back 10

medium

Front 11

water waves transfer energy through _____

Back 11

water

Front 12

Earthquakes transfer energy through _____

Back 12

earth

Front 13

light waves are transverse waves that need no ______ to transfer energy

Back 13

medium

Front 14

top of a wave

Back 14

Crest

Front 15

bottom of a wave

Back 15

Trough

Front 16

distance from crest to crest or trough to trough on a wave

Back 16

wavelength (λ)

Front 17

distance from crest or trough to the rest position of the medium

Back 17

amplitude

Front 18

the # of waves that pass a given point in a second

Back 18

frequency (ν)

Front 19

The units for frequency are the _____(Hz), cycles/second(cycles/s) or /second ( /s)

Back 19

Hertz

Front 20

speed a wave is travelling

Back 20

wave velocity

Front 21

transverse waves produced by the motion of electrically charged particles that travel through space at the speed of light—3.00 x 108m/s

Back 21

Electromagnetic Waves

Front 22

Electromagnetic waves are also called _____, _________, _______ ______, _______________ _________ because the waves radiate from the electrically charged particles

Back 22

light, radiation, radiant energy, electromagnetic radiation

Front 23

all forms of electromagnetic radiation move at a constant speed of about 3.00 x 10^8m/s through a ______ and slightly slower through ______

Back 23

vacuum; matter

Front 24

Since air is mostly space, the value of 3.00 x 10^8m/s is light's approximate speed through ___

Back 24

air

Front 25

Light wave velocity can be described by the formula:

Back 25

C = λ ν

Front 26

the speed of light, 3.00 x 108m/s

Back 26

C

Front 27

the wavelength of the wave in meters

Back 27

λ

Front 28

the frequency of the wave

Back 28

ν

Front 29

this represents an _______ __________ because if λ goes down, ν goes up and if λ goes up, ν goes down

Back 29

inverse proportion

Front 30

Together, all forms of EMR form the _______________ ________

Back 30

electromagnetic spectrum

Front 31

The greater the frequency or energy, the greater the ______

Back 31

danger

Front 32

The greater the _________, the smaller the __________

Back 32

frequency; wavelength

Front 33

radio waves have lowest _________, greatest __________

Back 33

frequency; wavelength

Front 34

Radio Waves are used in ____________

Back 34

communications

Front 35

used in cooking and communications

Back 35

microwaves

Front 36

Microwaves carry energy inside food to make the molecules move ______, heating the food

Back 36

faster

Front 37

this is the heat given off by everything on earth, living or not. Used in night vision, many devices such as t v remote controls and organisms such as pit vipers use it to find their prey

Back 37

infrared

Front 38

ROY G BIV is a small part of EMR

Back 38

visible light

Front 39

- harmful to skin if too much exposure
- helpful—used to treat skin disease, sterilize milk & water

Back 39

ultraviolet rays

Front 40

- used to see inside the body
- go through most muscle but are absorbed by bone

Back 40

X-rays

Front 41

- highest frequency, shortest wavelength
- most destructive yet some frequencies are used to treat cancer

Back 41

Gamma rays

Front 42

In the early 1900's, scientists conducted 2 experiments involving the interactions between light & matter that could not be explained by the ____ ______ __ _____

Back 42

wave theory of light

Front 43

___ ______ proposed that hot matter does not emit EMR continuously as would be expected if the light given off were in the form of waves

Back 43

Max Planck

Front 44

Instead Plank suggested that the light is given off in small, specific amounts called _____

Back 44

quanta

Front 45

_______ is the minimum amount of energy that can be lost or gained by an atom.

Back 45

Quantum

Front 46

In student terms, a quantum is a "______ __ ______"

Back 46

packet of energy

Front 47

the emission of electrons from a metal when light of a certain frequency shines on it

Back 47

Photoelectric Effect

Front 48

Electricity is a flow of _________

Back 48

electrons

Front 49

Mystery involved is why it took a certain ________ to work

Back 49

frequency

Front 50

If the light striking the metal had enough energy, then the _________ were knocked off

Back 50

electrons

Front 51

If the light striking the metal did not have enough ______ then the electrons were not emitted no matter how long the light shone on the metal

Back 51

energy

Front 52

It seemed that if light were in waves then any _________ would work to emit the electrons

Back 52

frequency

Front 53

Photoelectric effect explained by ______ ________

Back 53

Albert Einstein

Front 54

The photoelectric effect was expanded on Planck's theory of the _______

Back 54

quantum

Front 55

Said that EMR has a duel ____-________ ______

Back 55

wave-particle nature

Front 56

While light has wave-like properties, it can also be thought of as a ______ __ _________

Back 56

stream of particles

Front 57

Each particle of light carries a _______ __ ______

Back 57

quantum of energy

Front 58

Einstein called the particles _______

Back 58

photons

Front 59

a particle of EMR having zero mass and carrying a quantum of energy

Back 59

Photons

Front 60

the energy in a particular photon depends on the frequency of the _________

Back 60

radiation

Front 61

radio waves have lower frequency than gamma rays so a photon from a radio wave has less ______ than one from a gamma ray

Back 61

energy

Front 62

The _________ in atoms absorb energy from EMR

Back 62

electrons

Front 63

This increases the energy in the atom's electrons by a certain ______

Back 63

amount

Front 64

the relationship between the energy in a photon and the frequency of the radiation is represented by the formula:

Back 64

E = hν

Front 65

Amount of energy in the photon expressed in Joules

Back 65

E

Front 66

Planck’s Constant or 6.63 x 10^-34 Joules / seconds

Back 66

h

Front 67

stays the same

Back 67

constant

Front 68

Joules is a SI unit for ______

Back 68

energy

Front 69

frequency

Back 69

v

Front 70

this represents a ______ __________

Back 70

direct proportion

Front 71

If _ goes up, then _ goes up

Back 71

E; v

Front 72

If _ goes down, then _ goes down

Back 72

E; v

Front 73

the electrons in atoms ______ energy

Back 73

absorb

Front 74

Einstein said EMR is absorbed by matter only in:

Back 74

whole numbers of photons

Front 75

In order for an electron to be ejected from a metal’s surface, the electron must be struck by a single photon with the minimum energy needed to knock the electron loose. This minimum energy corresponds to a minimum frequency. If the photon's frequency is below the minimum, then the electron stays attached to the metal. Since electrons in different metals are bound more or less tightly, different metals require different frequencies to show the photoelectric effect

Back 75

note

Front 76

lowest energy state of an atom

Back 76

ground state

Front 77

the ground state is the most ______ state of an atom

Back 77

stable

Front 78

In the ground state, electrons occupy the ______ ______ ______ possible and carry the least amount of energy to stay in those levels

Back 78

lowest energy levels

Front 79

a state in which an atom has a higher energy state than it has in the ground state

Back 79

excited state

Front 80

In the excited state, electrons have ________ energy

Back 80

absorbed

Front 81

if electrons gain the right amount of energy, they jump to a ______ _____

Back 81

energy level

Front 82

When electrons absorb energy and move to higher Energy levels, the atom becomes ________

Back 82

unstable

Front 83

The atom returns to the ground state as the electrons give off the same amount of energy that they absorbed in the form of light (photons)

Back 83

electron transition

Front 84

Electrons can change energy levels only with _____ amounts of energy. If it only gains some of the energy it just spins faster and won't change ______ ______

Back 84

exact; energy levels

Front 85

Examples of electron transition in everyday include:

Back 85

- light bulbs
- fireworks
- neon lights

Front 86

pattern of EMR

Back 86

Spectra

Front 87

tool used to the study the structure of atoms and the composition of matter

Back 87

spectroscope

Front 88

A spectroscope uses ______ to separate light into a spectrum which can be examined

Back 88

prisms

Front 89

A spectroscope bends light different amounts according to its __________

Back 89

wavelength

Front 90

There are different types of spectra:

Back 90

- continuous spectrum
- discontinuous spectrum

Front 91

one color blends into the next because all frequencies of light within the range are being emitted

Back 91

continuous spectrum

Front 92

Each element has its own ____ _________ ________ that is like the element's finger prints

Back 92

line emission spectrum

Front 93

formed when excited atoms of an element are formed by passing electricity through its gas or vapor under ___ ________

Back 93

low pressure

Front 94

the color characteristic of the element is emitted as the electrons return to the ______ _____

Back 94

ground state

Front 95

Passing the color emitted by the element through a spectroscope produces the ____ _________ ________ for the element

Back 95

line emission spectrum

Front 96

We see narrow bands of color that correspond to the wavelengths of visible light given off by the element as it undergoes ________ __________

Back 96

electron transition

Front 97

There are also bands of _____ between the visible colors. These bands represent areas where no light is being emitted. Bands in the ___________ and ________ ranges are sometimes detected but not seen because they are not in the visible range

Back 97

black; ultraviolet and infrared

Front 98

Scientists studied the line emission spectrum for hydrogen first. As they tried to explain why not all colors were visible, they devised the _______ _________ _____ of the atom

Back 98

quantum mechanical model

Front 99

Bohr linked the atom's ________ with ______ _________

Back 99

electron; photon emission

Front 100

electrons circle in ______

Back 100

orbits

Front 101

electrons closest to the _______ have least amount of energy

Back 101

nucleus

Front 102

the farther the electron is from the nucleus, the _______ energy it has

Back 102

greater

Front 103

If an electron gains the right amount of energy, it can move to a ______ ______ _____

Back 103

higher energy level

Front 104

The electron has to gain the amount of energy equal to the difference between the higher-energy orbit and the initial lower-energy orbit. Based on the wavelengths of hydrogen's line emission spectrum, Bohr calculated the energies the electrons would have in the various energy levels.

Back 104

note

Front 105

It was soon realized that Bohr's model didn't explain the ____ _________ ______ for atoms with more than one electron and did not explain how chemical reactions occur

Back 105

line emission spectra