1. 5.2 QUANTUM THEORY AND THE ATOM PART 2 The quantum mechanical model of the atom

2. We left off with Bohr’s model of the atom. What did it do for us? What did it not do?

3. The quantum mechanical model of the atom successfully describes electrons in all elements, both conceptually and mathematically Like Bohr’s model, electrons can only exist ____________________ however- there are differences…

4. 1. In quantum mechanics, electrons are treated as _________________ (Bohr treated them as ___________________) De Broglie’s idea was that if light can have both wave and particle characteristics – _________________ (Note: this actually explains Bohr’s idea that electrons can only exist in certain energy levels.)

5. 2. Also, you can never know exactly where an electron is… you can only predict the probability of it being found in a certain area of space. Why is this so?

6. This is called the

7. The Principle states: The more you know about an electron’s _______and ________, the less you know about its___________, and vice versa Experimental evidence for the Principle Heisenberg was driving down the road, and was stopped by a police officer. “Sir,” says the officer, “do you know how fast you were going?!” Heisenberg says “no, but I know...” ( finish his sentence)

8. Schrodinger developed the These mathematically describe the electron as a wave, and they work for all elements

9. To review: The quantum mechanical model of the atom includes ideas from: *note: other scientists also contributed SCIENTISTHIS CONTRIBUTION BOHR DE BROGLIE HEISENBERG SCHRODINGER

10. How is the quantum mechanical model of the atom going to help us this year in our quest to understand how things happen in our world?

11. We will use the solutions to the Schrodinger wave equations which involve quantum numbers. Quantum numbers describe electrons, and areas where electrons may be found/how the electrons are arranged around the nucleus. In other words, from quantum numbers we can derive electron configurations Why are electron configurations important?

12. Remember – chemistry is based on electrons and how they are arranged; so determining electron configurations is the first step in explaining how chemistry – and the world - work!