chp 4 test Flashcards
types of electromagnetic radiation in order (electromagnetic spectrum)
radio waves microwaves infrared radiation visible light ultraviolet radiation x-ray gamma radiation
radio waves
least harmful
longest wavelength
shortest frequency
gamma radiation
most harmful
shortest wavelength
highest frequency
colors of visible light listed in order of increasing energy
ROYGBIV
red orange yellow green blue indigo violet
colors of visible listed in order of decreasing energy
VIBGYOR
violet indigo blue green yellow orange red
wavelength
the distance from one crest to the next
frequency
the number of waves that pass by a given point every second
how are wavelength and frequency inversely related?
longer wavelength we have shorter frequencies
shorter wavelengths have higher frequencies
electromagnetic radiation problems
c = yv e = hv
photoelectric effect
if the red light traveled as a wave, eventually the metal would have soaked up enough energy and conducted a current (but it didn’t)
only the purple light generated a current because only its bundles of energy are energetic enough to cause the electrons to move
conclusion: light travels in a stream of particles called photons
light has a dual wave particle nature: sometimes it travels as a wave and sometimes it acts like a stream of particles
quanta
a “hot” object that radiates energy in small, specific amounts (proposed by max planck)
photon
a quanta of light
quantized vs continuous
quantized- only certain, specific values are possible
continuous- any value is possible
spectroscopy
the identification of atoms by studying the emission spectra
emission spectrum
the series of lines that is seen through a spectroscope as an element is heated
excited state
when electrons gain energy and go to a higher energy level
ground state
when electrons lose energy and go to a lower energy level
heisenberg’s uncertainty principle
the position and speed of a moving object cannot both be measured at the same time
the act of observing the electron changes its behavior
electrons should not be thought of as well defined orbits
bohr model problems
it only works for hydrogen
could not explain the line spectra or elements with more than one electron
treats electrons as particles
similarities between the bohr model and the quantum model
the idea of quantized energy levels
orbit vs orbital
orbital- a region around the nucleus when an electron with a given energy is likely to be found; a high region of probability, not a definite location
orbit- a region around the nucleus when an electron with a given energy is certain to be found; a definite location
principle quantum number
description
describes the energy level of the orbital (bohr label as n)
principle quantum number
possible values
1 2 3 4 5 6 7 8
orbital (angular momentum quantum number
description
describes the shape of the orbital
