Welcome to Bonding OB: introduction to what bonding is, and learning to draw (lots of) Lewis Dot...
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Transcript of Welcome to Bonding OB: introduction to what bonding is, and learning to draw (lots of) Lewis Dot...
Welcome to BondingOB: introduction to what bonding is, and
learning to draw (lots of) Lewis Dot Diagrams. (remember that foreshadowing?)
Chemistry is a course about what stuff is, and how this stuff reacts with other stuff. If a reaction happens, then bonds were formed, and most likely, other bonds were broken to let this happen. There is a lot to chemistry, the energy required or released, the properties of all that stuff, the conservation of energy, conservation of mass, and even conservation of CHARGE (coming soon).
Atoms of the elements are bonded together to make new stuff. There are a variety of bond types, all with rules and reasons. We’ll examine lots of them, but please realize that there is always way more going on above our heads, and due to reasons we will not learn about in this course.
Types of bonds we will see:
1.Ionic - are bonds between cations and anions. The charges of the cations and anions will always net to zero. 2.Covalent - are bonds between two or more NON METALS. If there is a metal in the compound, it must be ionic. If there are no metals, then it’s covalent. 3.Metallic - these are the connection that metal atoms make with each other when solid metals exist. They give rise to all the properties of metals. One type of atom bonds to itself.4.Intermolecular - these are the kind of weak attractions between molecules. There are three different kinds of these, but two are nearly identical. I like these a lot.
Learning to draw Lewis Dot Diagrams. These will show us the outermost electrons, the VALENCE ELECTRONS, which are in the valence orbital. By reminding ourselves about these electrons it will help us to better understand what bonding can happen.
Bonds always* form when atoms or ions end up with full outer orbitals, like the noble gases. * of course there are exceptions, but not many, and we’ll get to them soon.
First:Dots will represent electrons. Lewis dot diagrams will only show valence electrons, not the inside electrons. The inside electrons do not participate in the bonding anyway.
The first orbital is tiny, it only holds 2 electrons at most.
The second orbital is bigger, it can hold only up to 8 electrons (with a few exceptions!)
We won’t be drawing atoms bigger than 2 orbitals in our class, but they will be added in college chemistry, so be patient.
Together we’ll draw a few atoms, and ions, then YOU will continue these charts which will run from hydrogen to calcium (20 atoms and 20 ions). You need to start on the top of a new page NOW.
Atom number
Atom symbolLewis Dot
(atom)Ion Symbol
Lewis Dot(ion)
1 H H+1
2 He
3 Li
4 Be
5 B
Together we’ll draw a few atoms, and ions, then YOU will continue these charts which will run from hydrogen to calcium (20 atoms and 20 ions). You need to start on the top of a new page NOW.
Atom number
Atom symbolLewis Dot
(atom)Ion Symbol
Lewis Dot(ion)
1 H H· H+1 [H]+1
2 He He: --- ---
3 Li :Li Li+1 [Li]+1
4 Be :Be: Be+2 [Be]+2
5 B :B Not in our class
Atom number
Atom symbol Lewis Dot Ion Symbol Ion Dot
6 C C Not in our class
7 N N N-3
8 O O O-2
9 F F F-1
10 Ne Ne --- ---
11 Na Na Na+1 [Na]+1
Atom number
Atom symbol Lewis Dot Ion Symbol Ion Dot
12 Mg Mg Mg+2 [Mg]+2
13 Al Al Al+3 [Al]+3
14 Si Si Not in our class
15 P P P-3
16 S S S-2
17 Cl Cl Cl-1
Atom number
Atom symbol Lewis Dot Ion Symbol Ion Dot
18 Ar Ar --- ---
19 K K K+1 [K]+1
20 Ca Ca Ca+2 [Ca]+2
Lewis Dot diagrams for atoms show only valence electrons.
Lewis Dot diagrams for ions show the NEW Valence Orbital Arrangement.