Presentation on theme: "Objectives To understand how the emission spectrum of hydrogen demonstrates the quantized nature of energy To learn about Bohr’s model of the hydrogen."— Presentation transcript:
1 ObjectivesTo understand how the emission spectrum of hydrogen demonstrates the quantized nature of energyTo learn about Bohr’s model of the hydrogen atomTo understand how the electron’s position is represented in the wave mechanical model
2 A. The Energy Levels of Hydrogen Only certain types of photons are produced when excited Hydrogen atoms release energy. Why?
3 A. The Energy Levels of Hydrogen Atomic statesExcited state – atom with excess energyGround state – atom in the lowest possible stateWhen an H atom absorbs energy from an outside source it enters an excited state.
4 A. The Energy Levels of Hydrogen Energy level diagramEnergy in the photon corresponds to the energy used by the atom to get to the excited state.
5 A. The Energy Levels of Hydrogen Only certain types of photons are produced when H atoms release energy. Why?
6 A. The Energy Levels of Hydrogen Quantized Energy LevelsSince only certain energy changes occur the H atom must contain discrete energy levels.
7 B. The Niels Bohr Model of the Atom (1913-1915) Bohr’s model of the atomQuantized energy levelsElectron moves in a circular orbitElectrons jump between levels by absorbing or emitting photons of a particular wavelengthAble to mathematically explain the emission spectrum of Hydrogen (compare with Rutherford)
9 B. The Bohr Model of the Atom Bohr’s model of the atom was not totally correct.Had difficulties with spectra of larger atomsElectrons do not move in a circular orbit and don’t seem to behave like discrete particles all the timeMaybe small particles, such as electrons, can also behave like waves having a dual nature (just like photons)……?
10 C. The Wave Mechanical Model of the Atom (de Broglie and Schroedinger – mid-1920’s) OrbitalsNothing like orbitsProbability of finding the electron within a certain space