Ionic Bonds Characteristics of an Ionic Bond Characteristics

Ionic Bonds

Characteristics of an Ionic Bond

Characteristics 1. High melting and boiling points For example melting points for two ionic: Na. Cl is 1413°C and Ba. Cl 2 is 962°C but covalent CH 4 is 182°C 2. Tend to be soluble (will dissolve) in water

3. Can conduct electricity in the molten state and when dissolved in water https: //phet. colorado. edu/en/simulation/leg acy/sugar-and-salt-solutions 4. Crystallize as sharply defined particles 5. Generally form between metals and nonmetals.

Ionic Bonding Terms and why do they bond.

Bonding Order The first atoms listed in the formula will have a positive charge (cations). The last groups of atoms listed will have a negative charge (anions).

Na. Cl b Na is the cation b Cl is the anion Be. Cl 2 b Be is the cation b Cl is the anion

NH 4 NO 3 b NH 4 is the cation - it is a polyatomic ion b NO 3 is the anion – it is a polyatomic ion Na 2 SO 4 b Na is the cation b SO 4 is the anion

Valence Review For the main group elements: b 1 valence for the alkali family b 2 valence for the alkaline earth b 3 for boron family b 4 for carbon family b 5 for nitrogen family b 6 for oxygen family b 7 for halogen family b 8 for noble gases, but He (has 2)

Drawing Lewis Dot for Elements Symbol of element is in the center b Dots are distributed around the symbol representing the total valence electrons b

b Atoms bond together to achieve noble gas configurations. b Energy must be put into the system to form a bond. b We have to provide some push (energy).

Bonding Steps 1. 2. A transfer of electrons occurs An electrostatic attraction

Examples Li and Cl Li and O

Metallic Bonding

Metallic Bonding v When several metal atoms come together to form a bond. v These types of bonds are weaker than ionic bonds. v They are weaker because electrons are not truly transferred to one atom. v Electrons are delocalized over all the atoms, creating a bond. v. Also called a sea of electrons model

Metallic or Ionic b Pb. O b Au. Au b Ionic b Metallic b Li. Na b Na. Fe b Metallic b metallic

Characteristics b Malleable – it can be hit and it will flatten out (or change shape) b Ductile – when it is pulled, it does not break but pulls out into a wire b Conductivity-ability to allow heat and electricity to flow through

Characteristics b Low volatility – it does not easily evaporate b Has metallic luster – are shiny

Characteristics and Delocalized Electrons Malleable, Ductile, and Conductivity are directly related to the delocalized electrons. Delocalized electrons are able to flow between any of the metal atoms