Valence electrons The number of electrons an atom has in its outermost shell Chapter 4 Text starts page 114

What happens to electrons  Most of the elements we’ve seen have 8 spots for electrons in their valence orbitals  If all 8 spots are filled with electrons, the atom is stable (unreactive). Atoms tend to react with each other until they reach a stable # of 8 electrons  Atoms with 5, 6, 7 valence electrons gain electrons from other atoms to reach 8 in their valence shell.  Atoms with 4, 3, 2, 1 electrons tend to lose their electrons to the atoms with 5 or more valence electrons, to empty their valence down to the next full level of electrons. When they get down to this full valence, then they’re stable, too. 

Valence electrons The number of electrons an atom has in its outermost shell

Bonding Ionic Bond vs Covalent Ionic This attraction is between 2 opposite charges.  Example includes formation of NaCl  Electrons are transferred in ionic bonding  Characteristics include compounds that make crystals, conduct electricity and have high melting points

Ionic Bond Occurs when opposites attract. Electrons are transferred Ionic Bond Intro Complete these questions after the Podcast 1. What do ionic bonds hold together? 2. What is an ion? 3. Name 4 examples of compounds held by ionic bonds 4. What makes NaCl stick together? Explain.

Bonding Ionic Bond vs. Covalent  Covalent Bonding  A chemical bond that forms when 2 elements share electrons  Usually forms between non metals  Often include oxygen, carbon, nitrogen and halogens.  Atoms are attracted and share electrons at same time

Covalent Bonds A bond that forms when 2 elements share electrons Both atoms are attracted to the electrons at the same time Complete workbook pages 43-48

Podcast calculating valence electrons Visit the site Practice Periodic Tablehttp://

Electron Configuration Table

Practice Electron Configuration