You need: Chemical Bonding ArticleYellow Chemical Bonding

paper

Is your spiral turned in??? Do it NOW!

Unit 6

Fold your yellow paper like a letter… HURRY!

You have 15 minutes to read the Chemical Bonding article and

transfer the info learned into the right section of the brochure

And go….

Time’s Up!

Now check to see if you got the same thing I got…

Include my drawings if you didn’t have time to draw any from the article

Take good notes –> assignment will be easy!

A chemical bond is:An attraction between the nuclei and valence electrons of different atoms that holds the atoms together (the hook up!!!)

Why do atoms bond? (outer flap)

Most elements (besides noble gases) are very unstable When they bond they become more stable (like a noble gas)

Everybody has their 8!!!

They had to share to help

each other out.

How do atoms bond?atoms bond by gaining, losing, or sharing e-

Most Group A elements (s and p - block) want to attain an octet (8 valence e-)

Octet Rule – most elements want to have 8 valence electrons to achieve stability

Types of bonding (open flaps)

1. Ionic BondsTransfer e- from a metal to a nonmetalSmallest ratio is called a formula unitExample (metal) CaCl2 (nonmetal)

Ionic Bond (draw & label this!)

Notice the pair of electrons is all the over on the right.

Higher electronegativityMore attractive!

+ +Metal nonmetal

e-

e- e-

e-

2. Covalent

sharing of e- between 2 nonmetals

Smallest ratio of a covalent compound is called a molecule

Examples: H2 H2O & C6H12O6

2 types of covalent bonds:(draw pics too)

Nonpolar covalent

Equal sharing of e-

Example: H2

Polar covalent

Unequal sharing of e-

Notice right is pulling harder

Example: HCl

+ +=

+ +

Polar Covalent Bondelectrons shared unequallyChlorine has higher electronegativity (EN) so it pulls harder

HCl Hydrochloric acid

3. Metallic Bonding

All involved atoms are metals (duh!) Electrons are shared in a “sea of free

flowing or mobile electrons” by all atoms

This flow is responsible for ductility, malleability, luster and ability to conduct heat and electricity

Example: copper wire

The “sea” of electrons

2 ways to determine bond type (fold up your bottom

flap)

1. Location on the periodic table metal + nonmetal = Ionic nonmetal + nonmetal =

Covalent metal + metal = Metallic

2. taking the difference in the electronegativity (subtract!!!)

Sulfur and Hydrogen 2.5 – 2.1 = 0.4

Nitrogen and Cesium 3.0 – 0.7 = 2.3

Chlorine and Bromine 3.0 – 2.8 = 0.2

Polar covalent

Ionic

Nonpolar covalent

4.0 ionic 1.7 polar cov 0.3 nonpolar cov

Now you try…

Electronegativity & Bond Type Homework

Don’t forget Chemis-Tree project!!! Google ideas! Look what I found online…

Happy Thanksgiving!!!I am thankful for each of you. It’s crazy to me that I get paid to do something I love. I love your personalities, your laughter, your passion about life and your face when you’re successful at learning something difficult. Be safe next week and don’t eat too much! Love ya! Duley