Welcome to Chemistry Welcome to Chemistry Turn in electron configuration Turn in electron configuration Notes on Bonding Notes on Bonding Practice Practice

Warm up Write noble gas configuration for Cu and Ag Write noble gas configuration for Cu and Ag

Introduction to Chemical Bonding Chapter 6, Section 1 Get ready to take notes

What is a bond? A bond is an electrical attraction between valence electrons and protons of different atoms A bond is an electrical attraction between valence electrons and protons of different atoms

Why bond? Nature likes things easy (ie. low energy) and bonding causes atoms to be more stable. Nature likes things easy (ie. low energy) and bonding causes atoms to be more stable.

2 Main types of bonds Covalent – electrons are shared between nonmetals Covalent – electrons are shared between nonmetals Ionic – electrons are transferred from cation to anion Ionic – electrons are transferred from cation to anion –Might want to refresh your memory on electronegativity (p. 151)

What determines type of bond??? Electronegativity! Electronegativity! –Subtract the EN of the 2 atoms, then... If difference is equal to or more than 1.7 = ionic If difference is equal to or more than 1.7 = ionic If difference is btwn 0.3 & 1.7 = polar covalent If difference is btwn 0.3 & 1.7 = polar covalent If difference is less than 0.3 = non-polar covalent If difference is less than 0.3 = non-polar covalent

What were those bonds again? Ionic = electrons are transferred Ionic = electrons are transferred Polar Covalent = electrons are shared, but not equally Polar Covalent = electrons are shared, but not equally Non-polar covalent = electrons are shared equally Non-polar covalent = electrons are shared equally

How ‘bout some examples? What type of bond would form between the following elements? What type of bond would form between the following elements? –Hydrogen & Sulfur –Cesium & Fluorine –Carbon & chlorine –2 Oxygen atoms

Practice S and H S and H – =0.4 –polar covalent (b) Cs and F Cs and F – =3.3 –Ionic (c) C and Cl C and Cl – =0.5 –polar covalent (b)

Practice Ca & Cl Ca & Cl – =2.0 –Ionic (c) O & O O & O – =0.0 –nonpolar covalent (a) Cl and Br Cl and Br – =0.2 –nonpolar covalent (a)