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I. Indeterminacy and Probability Distribution Maps A. Newton’s classical mechanics laws for particle behavior are deterministic We can predict exactly where a macroscopic particle is going to go if we know where it’s been This behavior correlates with what we see in everyday behavior of objects B. Quantum Mechanics is based on Uncertainty and Probability: Indeterminate We can’t predict exactly where an electron is going, or even where it is right now This behavior does not correlate to everyday objects, but correctly predicts small particle behavior Solutions to the Schrodinger Equation There are many, quantized solutions These solutions are related through Quantum Numbers that are the results of how the solutions are arrived at. These Quantum Numbers will eventually help us explain the shapes of orbitals, as well as the format of the Periodic Table Preview: II. Quantum Numbers (QN) Principal QN (n = 1, 2, 3, . . .) Related to size of the atomic orbital (distance from the nucleus). Larger n value indicates higher energy Larger n value means electrons are less strongly bound to nucleus Angular Momentum QN (l = 0 to n ? 1) Relates to shape of the atomic orbital. Each l number is assigned a letter n = 3, l = 0, 1, 2 (s, p, and d orbitals in the third shell) Magnetic QN (ml = l to ? l) Relates to orientation of the orbital in space relative to other orbitals. 2. For l = 2, ml = -2, -1, 0, 1, 2 (Five d-orbitals) Electron Spin QN (ms = +1/2, ?1/2) Relates to the spin states of the electrons. Electrons are –1 charged and are spinning Spinning charge creates a magnetic field You can tell the direction of the spin by which way the magnetic moment lines up in an external magnetic field The two possible spin directions are called +? and –? Pauli Exclusion Principle In a given atom, no two electrons can have the same set of four quantum numbers (n, l, ml, ms). 2. Therefore, an orbital can hold only two electrons, and they must have opposite spins.