Ch 7 Notes Flashcards
Electromagnetic Radiation
Radiant energy
A form of energy which has wave characteristics and moves through a vacuum at the speed of light
C = λ • v
speed of light = wavelength • frequency
Amplitude
Height of a wave
Node
Point of 0 amplitude
Distance between 2 nodes is half a wavelength
What does Planck’s Equation state?
Energy of a vibrating system is proportional to the frequency of vibration
Photon
The smallest particle of light
As frequency (v) increases
Energy (E) increases
As wavelength (λ) decreases
Energy (E) increases
Principal Quantum Number
Shell
Distance from nucleus
Size of orbital
Angular Momentum Quantum Number
Subshell
Shape of orbital
Magnetic Quantum Number
Orientation of orbital within subshell
The energy of the electron in the atom is?
Quantized
Gamma rays have the highest energy and smallest wavelength and high frequency
Radio waves have less energy and longer wavelengths and low frequency
Wavelength (lambda)
Distance between successive waves
Frequency (v)
Number of complete wavelengths or cycles passing a given point in 1 second
ROY G BIV
Violet more energy
Red longer wavelength
E = h•v
Energy = Plancks Constant • Frequency
Monochromatic
Light of only one wavelength
Energy possessed by a single electron in the nth orbit of H atom
(equation)
En = - (Rhc) / (n•n)
Rydberg constant • Plancks constant • Speed of light
En = - (Rhc) (Z•Z) / (n•n)
Multiply by the atomic number squared to give you the energy of an electron in a different element
Why does the energy of an electron have a negative value?
Coulombs law
Attraction between oppositely charged bodies
As the energy of an electron becomes more negative?
The attraction becomes stronger
The energy of an electron becomes less negative when?
The quantum number increases
The distance between the electron and nucleus is greater
Ground state
Electron in n = 1 orbit
Closest to nucleus
Most negative energy
Excited state
Electron in an orbit when n > 1
Ionization Energy
Energy needed to remove a single electron from the atom
If the change in energy is positive?
Then energy is absorbed
The electron goes from a lower energy state to a higher energy state
If the change in energy is negative?
Then energy is emitted
The electron moves from a higher energy state to a lower energy state
The atomic spectra is?
The movement of electrons between quantized energy states
Describe the wave properties of the electron (equation)
de Broglie
Lambda = Plancks constant / (mass • velocity)
h/(m•v)
wave-particle duality
Particles can have properties of waves
Particle and wave properties cannot be measured at the same time
Uncertainty Principle
It is impossible to fix both the position of an electron and it’s energy with any degree of certainty
PROBABILITY
Energy is more important
Electron Density
The probability that an electron will be found at a location
High probability of finding an electron are high electron density areas
Orbital
A region of space where an electron of a given energy can most likely be found
Quantum Numbers
Integers that help define the location of where an electron is likely to be found
Value of l - Subshell label
0 - s
1 - p
2 - d
3 - f
Valence electrons
Electrons with highest value of n
