Bell Ringer How do we know how many valence electrons an atom has? What happens during ionic...

Bell RingerHow do we know how many

valence electrons an atom has?What happens during ionic

bonding?What is holding an ionic molecule

together?What 2 classes of elements are

involved in an ionic bond?

Covalent BondingChapter 6.2 a

Chemical Bonding Ionic Bond – Force that holds cations

and anions together and which involves the transfer of electrons. Occurs between a metal and a nonmetal.

Chemical BondingWhat do you think will happen

when 2 nonmetals bond?Will there be a transfer of electrons?

Why?

FF

Covalent BondingWhen two nonmetals meet - one atom is

NOT strong enough to take electrons from the other! So they must share them Covalent Bond!

Covalent bond - is a chemical bond in which two atoms share one or more pairs of valence electrons.

Covalent BondingElectrons want to be in pairs – 4

pairs of 2 to fulfill the octet rule.

Paired electrons are ‘happy’!Unpaired electrons are ‘sad’

How it Works

+

How it works!

Sharing Creates a Bond

F F

Outer Level Still only hold 8!!!!

Electron Configuration & Lewis Dot Structures

All 3 figures represent the same thing!BAR = Bond of shared electrons

F F

F F F F

Diatomic means “two atoms”.

Atoms of same element share bonding electrons equally.

Balanced

Covalent Bonds

The Halogen H-O-N-ies The diatomic 7

F Cl Br I H O N

Covalent Bonds

Halogens

H-O-N-ies

Single Bond

FFF F OR

Each atom now “Feels Like” it has 8 valence electrons!

Single Bond =

• One Pair of e- Shared Between Two Atoms.• Each atom gives one e- to the shared pair

How Will These Two Bond?

Oxygen and Oxygen

O O

Double Bond

OR

•Two Pairs of Electrons are Being Shared•Each atom gives one e- to each shared pair

O O

O O

How Will These Two Bond?Nitrogen and Nitrogen

N NN

Triple Bond

OR

• Three Pairs of Electrons Being Shared

N N

N N

PracticeNCl3AsF3CF4CF2Cl2GeH4SiS2CH2OHSiNCSF2C2Br2

PracticeC2H6C2H4C2H2C3H8C3H4