Atomic structure part 4 quantum mechanics Quantum mechanics and the atom… sound like fun… Well… if fun is like hitting you hand with a hammer…

Quantum physics and the atom What subatomic particle (p+, n, e-) is responsible for “all” normal chemical reactions? Right. The quantum mechanical model of the atom focuses on the electron and how it behaves in the atom… yarp!

Quantum numbers and the electron This model of the atom has the electrons on “rings” called energy levels. NOT GOOD ENOUGH!!! It has been found electrons are doing much more complicated things… yarp p+ n

So we have quantum numbers Quantum numbers are a way of determining where a specific electron in an atom is…. How is that electron moving? How much energy does it have? It is pretty much nerdy battleship for electrons. yarpy

Quantum #’s (4 of them) 1. principle Quantum # “n” tells you what energy level an electron is on. “n” ranges from 1-7 Though it can go higher Higher the number Typically further from the nucleus Typically have more energy yarp

That is what these rings are showing you How many energy levels? Which one has e- furthest from nucleus? Which one has e- with the least amount of energy? p+ n

2. second quantum # = the general orbital shape (or flight path) the electron is moving as the e- moves around the nucleus. The “shape” not a physical thing… it is the repeated path of the electron! s = sphere yarp

p = dumbbell d = complex f = very complex yarp

Adding a layer… energy levels, shapes and electrons LetterShape# flight paths on 1 energy level Max # electrons

Looky look!!!! Notice anything? # of flight paths and shapes??

The third quantum number This quantum # locates an electron with the orientation of an orbital p x p y p z These are called ORBITAL SUBLEVELS yarp

Put the 3 quantum to work… 4d 5s 2p x 6p y What…. Has the most energy? Closest to the nucleus? Making a sphere? Shows the 3 rd quantum number? Which one has a dumbbell sublevel on the y axis? Any others Mr. S? yarp

the 4 TH quantum number This is the spin quantum number Like our planet… each electron rotates/spins around it’s own axis. Electrons paired up in the same orbital sublevel spin opposite of each other Up and down spin Clockwise and counter clockwise spins yarp

How do we show spin??? Up and down arrows… vectors… Why don’t you show some examples of how this works??? Dare to compare the electrons! 1s↑4p z ↓5f↑5d↑ Ask your questions Mr. S…. yarp

Why don’t electrons…. Well… collide and destroy all matter? What does the first quantum # tell you??? So won’t there be overlap??? Why no collide???? yarp

The shapes electrons take All of the shapes we have talked about… It is all about keeping the negative charge of electrons as far away from each other as possible p x p y p z Y to the arp

Atomic structure part 4 Putting the box diagrams into the fun of the funness of quantum numbers

Find the 4 quantum #s in this… 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y

Example 1 hydrogen 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y

Example 2 helium Pauli exclusion principle = no more than 2 e- can be in the same orbital sublevel. They spin opposite of each other yarp 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y

Example 3 Beryllium Auf Bau principle = you build up by filling lowest energy orbital sublevels first before move to higher energy sublevels yarp 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y

Example 4 carbon Hunds rule = orbital sublevels of equal energy each get 1 e- before pairing up in the same sublevel yarp 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y

Example 5 Bromine Now, use the 5 to teach them electron shorthand configuration yarp 1s 7s 2s 3s 4s 5s 6s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 4f 5f Atom nucleus I n c r e a si n g e n e r g y