·http://www.youtube.com/watch?v=JNPFR-22MPA·http://www.chemguide.co.uk/atoms/properties/atomorbs.html·http://www.chemguide.co.uk/atoms/properties/orbitsorbitals.html#top·http://www.chemguide.co.uk/atoms/properties/elstructs.html#top

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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=sMt5Dcex0kg 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.)

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6

Types of Subshells

S orbitals can hold 2 Electrons 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

3B 4B 5B 6B 7B 8B 8B 8B 1B 2B

3A 4A 5A 6A 7A

8Agroup # = # valence (outside) e-

d p

f

sRow=# shells

Electrons orbitals are represented by 4 shapes (S,P,D,F)

s p

d

f

Notice something different with d?

We Can represent the # of electrons in their shells in what is called- Electron

Configuration1s1

row # = shell #possibilities are 1-77 rows subshell

-s, p, d, or f4 subshells

group # = # valence e-possibilities are:s: 1 or 2p: 1-6d: 1-10f: 1-14Total e- should equalAtomic #, Why?

Lets try and figure out what shells are in Cl?

1

2

3

4

5

6

7

6

7

peri

od #

= #

e-

shells

1A

2A

3B 4B 5B 6B 7B 8B 8B 8B 1B 2B

3A 4A 5A 6A 7A

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:It does not go “in order”, you read the periodic table from

left to right.

1s 2s2 2p6 3p63s2 4s2 4p6 5s23d 5p6 6s24d 5d4f

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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:Ask 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?

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11

s1s2 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!!!