OpenStax Chapter 6 Key Term

Question 1

wave

Answer 1

oscillation or periodic movement that can transport energy from one point in space to another

Question 2

wavelength

Answer 2

distance from peak to peak or trough to trough

Question 3

frequency

Answer 3

the number of wave cycles (one complete wavelength) that can pass a given point in space in a given amount of time s^-1

Question 4

amplitude

Answer 4

maximum displacement from equilibrium

Question 5

hertz

Answer 5

unit for frequency

Question 6

electromagnetic spectrum

Answer 6

energy and frequency have a direct relationship
frequency and wavelength have a indirect relationship

Question 7

standing waves

Answer 7

constrained within a region in space
play important role in understanding electronic structure of atoms
have an integer number, n, of half wavelengths between endpoints

Question 8

quantization

Answer 8

only discrete values for a more general set of continuous values of some properties are observed

Question 9

nodes

Answer 9

points between the two end points that are not in motion
n-1 nodes, where n is the number of half wavelengths
energy increases with the amount of nodes

Question 10

blackbody radiation

Answer 10

sunlight consists of a range of broadly distributed wavelengths that form a continuous spectrum
blackbody - convenient, ideal emitter that approximates the behavior of many materials when heated

Question 11

ultraviolet catastrophe

Answer 11

classical prediction that the intensity of the radiation radiated by a blackbody would increase as the wavelength decreased

Question 12

photoelectric effect

Answer 12

electrons can be emitted from surface of metal when it is hit with light that has a frequency greater than the threshold
the kinetic energy of the emitted electron depends on the frequency of the light
even at lower intensity, light of the appropriate frequency can eject an electron

Question 13

photoelectric effect (conc.)

Answer 13

light consists of radiation or quanta or packets of EM radiation with energy proportional to frequency of light
the greater the frequency of the photon, the greater the KE of the emitted electron
light has wave and particle nature

Question 14

photon

Answer 14

particle of light

Question 15

wave-particle duality

Answer 15

light has wave and particle behavior

Question 16

line spectrum

Answer 16

heated solid, liquids, and condensed gases emit light of a range of frequencies to produce a continuous spectrum
heated gases emit light at discrete wavelengths; each emission line consists of a single wavelength

Question 17

Balmer

Answer 17

derived an equation that related the four visible lines in the hydrogen emission spectrum to whole numbers
n_f = 2

Question 18

Rydberg

Answer 18

developed an equation to reproduce all of the lines in the hydrogen spectrum

Question 19

Bohr’s model of the atom

Answer 19

assumed that electrons would not emit or absorb energy unless it moved from one level to another
energy emitted or absorbed would reflect the energy difference between levels
quantization of energy
rearranges the Rydberg equation/derived an equation for the energy of an electron in hydrogen-like atoms and ions

Question 20

ground state of the electron

Answer 20

lowest energy state of the electron

Question 21

excited state of the electron

Answer 21

higher energy states of the electrons

Question 22

deBroglie wavelength

Answer 22

extended the wave particle duality of light to material particles
wavelength = h/p
Bohr’s idea only applies if electrons are considered circular standing waves
2pir=nlambda

Question 23

Davisson and Germer

Answer 23

electrons can behave as waves

Question 24

Heisenberg Uncertainty Principle

Answer 24

it is impossible to determine simultaneously and exactly the momentum and the position of a particle

Question 25

Schrodinger

Answer 25

described electrons as wavefunctions
three-dimensional stationary waves
reproduced Bohr’s expression for energy and the Rydberg formula

Question 26

Max Born

Answer 26

electrons are still particles
waves are not physical waves but complex probability molecules
the square of the magnitude of a wavefunction describes the probability of a particle being near a location in space
wavefunctions can be used to determine the distribution of electron density with respect to the nucleus

Question 27

principal quantum number

Answer 27

the quantum number on which the energy of the electron principally depends on
determines the size of the shell and the distance from the nucleus

Question 28

angular momentum quantum number

Answer 28

specifies the subshell and the shape of the orbital
0 = s
1 = p
2 = d
3 = f

Question 29

magnetic quantum number

Answer 29

specifies the orbital’s orientation in space
adopts values: -l…0…+l

Question 30

spin quantum number

Answer 30

specifies the spin of the electron
ms = +1/2 or -1/2

Question 31

atomic radius

Answer 31

increases down a group (more energy levels)
decreases across a period (valence electrons being added to the same energy level while proton number increases makes nucleus pull electrons closer)

Question 32

ionization energy

Answer 32

energy that is required to remove an electron from an atom
decreases down a group (added energy levels makes electrons easier to remove since there is more shielding)
increases across a period (nucleus pulling electrons closer together makes it harder to remove them)

Question 33

electron affinity

Answer 33

energy change associated with added an electron to a gaseous atom
- = wants to accept an electron
+ = does not want to accept an electron

Question 34

B and O exceptions to IE

Answer 34

B: 2s subshell has a higher effective nuclear charge since there is a possibility of the electrons being found near the nucleus, so the 2p1 electron is easier to remove
O: half-filled subshell has some stability associated with it, pairing energy - energetic cost associated with adding an electron to a pre-existing orbital with an electron