CHEM 1211 Lecture 16Outline of Last Lecture I. Electromagnetic RadiationA. Emission SpectrumB. Absorption SpectrumC. Bohr Model of AtomII. Predicting Emission Lines of HydrogenA. Rydberg EquationIII. Electronic TransitionsA. Wave nature of electronsOutline of Current Lecture I. Orbital Quantum Number1. Clicker Question One2. Clicker Question Two3. Clicker Question ThreeA. The S OrbitalB. The P OrbitalC. The D Orbital II. Spin Quantum Number1. Clicker Question FourCurrent Lecture: I. Orbital Quantum Number- An atomic orbital is defined by three quantum numbersN: shell principleL: Angular Momentum Quantum NumberMl: Designates an orbital within a shell- Electrons arranged in shells and subshells made of orbitals- You cannot figure out Ml without L or L without N.1. Clicker Question One: Calculate Enthalpy H°f for H2S(g) given that;Enthalpy H°fO2: 0 KJ/molEnthalpy H°fSO2: -296.8 KJ/molEnthalpy H°fH2O: -285.8 KJ/molEnthalpy H°298: -1124 KJ/molAnswer: -20.6 KJ2. Clicker Question Two: Which is not a possible value for the principle quantum number?A. 4B. 2C. 1200D. 03. Clicker Question Three: Consider the third shell in Hydrogen. How many values ofthe angular momentum quantum number would be possible?A. 0B. 1C. 2D. 3E. 4A. The S Orbital- The 1st shell has n=1 (lowest energy) SO: l=0, ml=0- Since ml has a single value, the subshell has a single orbital - This subshell is labeled S and we call this orbital 1S: it has a spherical shape- State with the lowest energy state first when dealing with electronsB. The P Orbital- For n=2, l= 0 and 1- Two types of orbitals, 2 subshells - For l=0, ml= -1, 0, 1 (this is the p subshell with three orbitals- When l = 1, there is a planar node through the nucleus- Planar node: spot on orbital where the probability of find the electron is zero- Px = Py = Pz: Degenerate (have same energy)C. The D Orbital: third shell (2 planar nodes) - For l=2, ml= -2, -1, 0, 1, 2 (D subshell with five orbitals!)- Number of nodes = value of angular quantum number (l)- There are n2 orbitals in the nth shell.II. Spin Quantum Number- Last Quantum number is the spin quantum number, Ms- The spin quantum number values: Ms = +1/2 or -1/2- Quantum number tells us the spin and orientation of the magnetic field of the electron- Wolfgang Pauli (1925): Exclusion Principle- NO two electrons in an atom can have thesame set of four quantum numbers- Orbitals can only have two electrons max.- Doesn’t have to have two electrons though.1. Clicker Question Four: Which of these subshell types isn’t possible?A: 5s: n=5, l=0B: 4p: n=4, l=1C: 3d: n=3, l=2D: 2d: n=2, l=2E: 2p: n=2,
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