Chemical Bonds

8th Grade Physical Science--California State Standards
Chemical Bond
The joining of 2 or more atoms by their electrons
Ionic Bond
Chemical Bond--Transfer of electrons
Covalent Bond
Chemical Bond--Sharing of electrons
2 or more ATOMS chemically combined
2 or more DIFFERENT ELEMENTS chemically combined, a pure substance
Properties of Compounds
Completely different properties than the elements in them
Electron Shells
Layers of electrons, 1st layer maximum of 2 electrons, then 8....
Valance Electrons
Outermost ring of electrons, able to form chemical bonds.
Octet Rule
Atoms like to have 8 Valance Electrons
Noble Gases
Have complete valance electron shells so they usually do not form bonds.
Chemical formula
Chemical symbols, and subscript numbers that describe a molecule or compound
Strong Bonds
Covalent Bonds (strength)
Weaker Bonds
Ionic Bonds (strength)
High Melting Point
Ionic bonds (have you ever melted salt with heat?)
Low Melting Point
Covalent bonds (butter is fat, fat is covalent bonds, is it easy to melt?)
Types of Elements in Covalent Bonds
Bonds between 2 or more Non-Metals
Types of Elements in Ionic Bonds
Bonds between Metals and Non-Metals
Poor Conductor
Covalent Bonds electrical conductivity
Good Conductor
Ionic Bonds electrical conductivity
Metallic Bonds
Bonding where electrons are shared and FREELY move around