Chapter 4: Light and Electronic Structure Flashcards
electromagnetic radiation
energy traveling in waves from charged particles
electromagnetic spectrum
the complete range of electromagnetic waves placed in order of increasing frequency
visible spectrum
small band of electromagnetic radiation we perceive as light
wavelength (𝜆)
distance between two consecutive wave points; measured in meters or nanometers
frequency (𝜈)
number of waves passing a point per second
hertz (Hz)
the unit of frequency, equal to one cycle per second; 1s^-1
wavelength and frequency relationship
inversely related to each other; as the wavelength decreases, the frequency increases & vice versa
speed of light (c)
𝜆𝜈, equal to 3.00 × 10^8 m/s
photon
small packet of light energy
energy of a photon (E)
E = hν or E = hc/λ
Planck’s constant (h)
6.63 × 10^-34 J·s, relates energy and frequency
line spectra
the emission of light only at specific wavelengths
Niels Bohr
physicist who proposed that electrons orbit the nucleus in the same way that planets orbit around the sun, orbits that were closer to the nucleus were lower in energy; he also proposed that electrons can jump from one energy level to another by absorbing light
Bohr model
model explaining emission spectra with energy levels
energy levels
discrete levels where electrons reside
quantum model
model that describes electrons as both particles and waves; indicates where electrons are most likely to be found
uncertainty principle
the idea put forth by Werner Heisenberg that the behavior of subatomic particles is uncertain; it is impossible to know the exact velocity and location of a particle
principal quantum number (n)
whole number indicating energy level of electrons
sublevel
energy levels divided into s, p, d, f
orbital
region where electrons are likely found
Aufbau Principle
electrons fill lowest energy levels first
Pauli Exclusion Principle
no more than two electrons per orbital
Hund’s Rule
single electrons occupy orbitals before pairing
electron configuration
arrangement of electrons in an atom’s orbitals
noble gas shorthand
abbreviated electron configuration using noble gases
valence electrons
electrons in the outermost shell involved in bonding
inner electrons
electrons not involved in bonding, lower energy
outer electrons
electrons beyond the noble gas configuration
octet rule
atoms prefer to have eight electrons in valence shell
energy level 1 (n=1)
contains one s sublevel, holds 2 electrons
energy level 2 (n=2)
contains one s and one p sublevel, holds 8
electrons
energy level 3 (n=3)
contains one s, one p, and one d sublevel - holds 18 electrons
energy level 4 (n=4)
contains one s, one p, one d, and one f sublevel - holds 14 electrons
ion electron configuration
adjust configuration based on ion charge
relative energy levels
energy increases in the order s<p<d<f
