Chemistry Honors – Class 32

Glorious Lewis Dot Structures!

Dates

• Period A: Thursday, October 29th
• Period B: Thursday, October 29th
• Period F: Friday, October 30th

Bonding

• Bond Polarity Examples
• Ch. 8 (27, 29, 33, 34, 35)

Lewis Structure

• putting together ideas about bonding
• drawings represent valence electrons (they bond)
• ionic v covalent representations
• ionic = use brackets (no sharing) with charge
• Lewis structures are NOT for 3D representations

Lewis Structures Steps

• count total valence electrons
• identify central atom
• arrange atoms outside of central atom evenly
• bond each atom once
• subtract bonding electrons from total
• arrange remaining electrons to “make happy” (“happy” = formal charge equal zero)

Notes

• bond = two dots = one line (shared)
• “octet” only ALWAYS applies to CNOF
• OK to have more than 8 (or less)
• F, H only bond once
• Carbon NEVER has lone pairs
• electrons always placed in pairs
• use FORMAL CHARGE to check work (#brought – #assigned)

Homework

• No HW