Chapter 7 notes
Chapter 7 notes General Chemistry 0110
Popular in General Chemistry 1
Popular in Chemistry
One Day of Notes
verified elite notetaker
This 4 page Class Notes was uploaded by Grace Lee on Wednesday March 11, 2015. The Class Notes belongs to General Chemistry 0110 at University of Pittsburgh taught by in Fall2014. Since its upload, it has received 102 views. For similar materials see General Chemistry 1 in Chemistry at University of Pittsburgh.
Reviews for Chapter 7 notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 03/11/15
General Chemistry 0110 Chapter 7 Notes A The Wave Nature of Light a b c g Wave continuously repeating change or oscillation in matter or in physical eld Electromagnetic radiation visible light x rays radio waves Wavelength lambda distance between any two adjacent identical points of a wave i Distance between two adjacent peaks Frequency v number of wavelengths of that wave that pass a xed point in one unit of time usually one second i 1s 51 or Hertz H At given speed wavelength and frequency are inversely related V x lambda is totally length of wave that has passed a point in 1 sec i Speed cv x lambda Electromagnetic Spectrum range of frequencies or wavelengths of electromagnetic radiation B Quantum Effects and Photons a b Thomas Young shows light can be diffracted diffraction property of waves in which the waves spread out when encountered an obstruction or hole the size of the wavelength Albert Einstein and photoelectric effect light has wave and particle properties i E oscillation nhv 1 H is Planck39s Constant physical constant relating energy and frequency 663e34 2 N is some whole number value quantum numbers vibrational energies are quantized possible energies are limited to certain values 3 Hv is vibrating energy ii Photons particles of electromagnetic energy with energy E proportional to the observed frequency of the light 1 E hv iii Photoelectric effect ejection of electrons from the surface of a metal or from another material when light shines on it 1 Ejected only if certain threshold value is exceeded 2 When photon hits metal energy hv is taken up by electron 3 When photon is not a particle it is absorbed 4 Work function minimum amount of energy that photon can have and still eject electron from a material 5 If photon has energy greater than work function excess energy appears as kinetic energy iv Waveparticle duality wave and particle pictures of light are complementary physical views C The Bohr Theory of the Hydrogen Atom a Continuous Spectrum spectrum containing light of all wavelengths b Line Spectrum spectrum showing only certain colors or speci c wavelengths of light i When shone through prism gives different lines of colors with different wavelength 1 4 lines in hydrogen atom ii 1lamda 1097 x 10e7m12quot2 1nquot2 1 n is whole number greater than 2 c Bohr postulates stability of hydrogen atom and line spectrum of atom i Energy level postulate Energy levels speci c energy values in an atom 1 Atom can only have speci c total energy values 2 E Rnquot2 a N 123 for H atom principal quantum number b R Rydberg constant in energy units i 2179 x 10e18 3 Energies are negative because energy of separated nucleus and electron is zero when nucleus and electron come together to form stable state energy is released ii Transitions between energy levels 1 As electron goes down energy level loses energy and emitted as a photon 2 Change in energy Rnquot2 nal Rnquot2initial R1nquot2 1nquot2 3 Energy of emitted photon hv delta E E nal Eintial d Emission of light electron moves from upper to lower energy level i Kinetic energy gained from collisions boosting energy and making electrons excited e Absorption of light i When decreasing energy levels photon of red light emitted and absorbed up hydrogen atoms D Quantum Mechanics a Quantum mechanics theory that applies to submicroscopic particles of matter such as electrons Momentum of photon is related to wavelength De Broglie relation wavelength hmv Quantum mechanics wave mechanics the branch of physics that mathematically describes the wave properties of submicroscopic particles i Impossible to know position and momentum of a particle ii Uncertainty principle a relation that states that the product of the uncertainty in position and momentum of a particle can be no smaller than Planck s constant divided by 4pi 1 Change in xChange in p gt h4pi 2 Change in xChange in v gt h4mpi Wave function mathematical expression about energy levelpsD Psiquot2 is probability of nding a particle within region of space i Psiquot2 is large near nucleus small on outside but never reaches 0 no de nite boundary of atom ii Finding electron within a shell is greatest at some distance from nucleus E Quantum numbers and Atomic Orbitals a 4 different quantum numbers speci c to wave function that shows where electrons are i 3 numbers bc 3 dimensions in space ii 1 number refers to magnetic property called spin Atomic orbital a wave function for an electron in an atom Principle Quantum number N Quantum number is the one on which the energy of an electron in an atom principally depends it can have any positive value 1 2 3 i Energy depends on n ii Size of orbital depends on n Angular Azimuthal momentum Quantum number I quantum number distinguishes orbitals of given n having different shapes it can have integer from 0 to n1 i Except for h atom energy also determined by l quantum Magnetic Quantum number M this quantum number distinguishes orbitals of given n and I that is of given energy and shape but having a different orientation in space allowed values are integers from to l i All orbitals have same energy different orientations ii 2 1 orbitals in each subshell f Spin Quantum number quantum number refers to the two possible orientations of the spin axis of an electron possible values are 5 and 5 i Spinning electron gives charge magnetic w north and south poles ii Orbitals in same subshell have same energy g S orbital spherical shape i ls orbital electron most likely found ii 25 orbital two regions h Three p orbitals two lobes arranged along a straight line with nucleus between lobes differ in orientation i Different angles orbitals denoted as 2px 2py 2pz 1 2px has greatest electron probability along x aXIs i D orbitals more complicated than 5 an p
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'