Chemical Bonding

By the end of this lesson you will be able to: Name and describe the 3 types of bonds and how they are different List possible compounds in each and how elements are affected by the bonds they share Describe how we know these bonds exist. What are properties of the bonds?

Ionic Bonds Bond most often between a metal and a nonmetal Transfer of electrons from the metal to the nonmetal Electrical attraction between large numbers of cations and anions called clusters Ion = a charged particle

Ionic Bonds Cation = + charged particle Loves to give electrons away Low Ionization Energy, Electron Affinity & Electronegativity Typically are metals Most metallic element = Fr

Ionic Bonds (cont.) Anion = - charged particle Loves to accept electrons High Ionization Energy, Electron Affinity & Electronegativity Typically are nonmetals Most nonmetallic element = F

Ionic Bonds (cont.) If a bond is ionic: The compound is solid The compound will fall apart (dissociate) into its original ions when dissolved in water -If a conductivity test is performed, the light bulb will… light! -EN values 1.8 up to 4

In General Ionic Bonds are the strongest bonds there are

Covalent Bonds Formed when 2 nonmetal atoms share electrons Can be liquid, solid or gas

Polar Covalent Bonds Unequal sharing of electrons Electrons attracted more to higher E.N. atom Electronegativity difference range = 0.3 – 1.7 (for polar covalent bonds) Polar Covalent Bonds dissolve in water Why? (Check out page 19 in your packet for EN of water) The light bulb doesn’t light up.

Non-polar Covalent Bonds Equal sharing of electrons Electronegativity difference range = 0.0 – <0.3 Usually found between diatomic molecules – two of the same atoms Non-polar covalent bonds don’t dissolve in water.

Metallic Bonds Bond formed between 2 metal atoms. Excellent electrical conductors in solid state Electrons are free to move within electron clouds of all metal ions = Sea of Electrons

Metallic Bonds In metals, p-orbitals and some d-orbitals are completely vacant and overlap each atom. Electrons are delocalized – they don’t belong to any one atom anymore.

Quick Review Ionic bonds are between Answer A) metals and non-metals B) non-metals C) metals Answer A) metals and non-metals

Quick Review Covalent bonds are between Answer B) non-metals A) metals and non-metals B) non-metals C) metals Answer B) non-metals

Quick Review Metallic bonds are between Answer C) metals A) metals and non-metals B) non-metals C) metals Answer C) metals

Quick Review The strongest bonds are between A) metals and non-metals B) non-metals C) metals Answer A) metals and non-metals (ionic)

Quick Review Ionic bonds at room temperature are Answer A) solid B) liquid C) gas D) any Answer A) solid Can you name some?

Quick Review Covalent bonds at room temperature are Answer D) any A) solid B) liquid C) gas D) any Answer D) any Can you name some? HCl (aq), Bromine (aq), Fluorine (g), Diamond (s)

Quick Review Metallic bonds at room temperature are A) solid B) liquid C) gas D) any Answer A) solid and B) liquid What metallic bonds can be liquid at room temperature? Hg Any ideas why? Bond strength not enough to make a solid yet strong enough to keep it from being a gas.

Quick Review Which bonds dissociate in water (water is polar)? A) ionic B) polar covalent C) nonpolar covalent D) Metallic Answer A) ionic