What Does an Atom Look Like? 3 Draw what you think N looks like in the box below... What is wrong with this diagram? What do the circles really represent?
Why have we been taught circles...and that electrons travel in perfect orbits? ·Circles are not actually wrong, they are just misrepresented when they are taught by some people. ·The truth is that circles are meant to represent energy levels of the electrons around the nucleus, not necessarily the paths the "follow" around the nucleus. ·As electrons get further and further away from the nucleus, they have more and more energy, because they are less "drawn in" by the nucleus.
Here is what electron clouds in an Atom really look like... http://www.youtube.com/watch?v=sMt5Dcex 0kg Electrons travel in Subshells, known as Orbitals. These are not ORBITS, but they are ORBITALS. The electron has a 95% probability that it is within its designated orbital
Heisenberg Uncertainty Principle ·Says, loosely, that you can't know with certainty both where an electron is and where it's going next. ·What it actually says is that it is impossible to define with absolute precision, at the same time, both the position and the momentum of an electron.) 4
6 Types of Subshells S orbitals can hold 2 Electrons P orbitals can hold 6 Electrons S orbitals can hold 2 Electrons
1 2 3 4 5 6 7 6 7 1A 2A 3B4B5B6B7B8B 1B2B 3A4A5A6A7A 8Agroup # = # valence (outside) e- d p f s Row = # shells Electrons orbitals are represented by 4 shapes (S,P,D,F) s p d f
We Can represent the # of electrons in their shells in what is called- Electron Configuration 1s1 row # = shell # possibilities are 1-7 7 rows subshell- s, p, d, or f 4 subshells group # = # valence e- possibilities are: s: 1 or 2 p: 1-6 d: 1-10 f: 1-14 Total e- should equal Atomic #, Why?
1 2 3 4 5 6 7 6 7 period # = # e- shells 1A 2A 3B4B5B6B7B8B 1B2B 3A4A5A6A7A 8Agroup # = # valence e- d f 3d 4d 5d 6d 4f 5f Subshells d and f are “special”- They are each staggered by one row. So for row 4, they are actually 3d, not 4d!
Try and write them out in order, you can stop with 6s.
Order of Electron Subshell Filling: I t does not go “in order”, you read the periodic table from left to right. 1s 2s22p6 3p6 3s24s2 4p6 5s2 3d 5p6 6s2 4d 5d4f
10 The Electrons in an atom can be show with letters and numbers (Electron Configuration), or also with boxes (Ground State Configuration). They show the same information, just a different representation. ·Electrons are represented here in boxes with up and down arrows. ·Electrons will try and "space" out in the available boxes, so you fill them one at a time. ·Electrons like their space because their charges repel each other.
Practice: A sk these questions every time you have to write an electron configuration ·Lithium: · find the element on the periodic table ·what is the period number? ·how many shells? ·what is the group number? ·how many valence electrons? ·what subshell(s) does Li have? ·what is the electron configuration? 2 2 1 1 s 1s 2 2s1
Now it can get annoying to write out all of these Electron Configuration for the elements further down on the periodic table! So fortunately there is a shortcut! Instead of writing it all out, you can first write the name of the "last" Nobel gas in brackets, and then do the Electron Configuration from there. First Draw the Electron Configuration for Zn...
http://www.youtube.com/watch?v=JNPFR- 22MPA Watch this video, it is basic, but really helps break down the steps...while watching the video, think of how YOU could make it better, because that will be your project for the rest of the week!!!