Atoms gain, lose, or share electrons until they have a stable octet.
There are 3 types of Bonding.
1) Ionic Bonds. An Ionic bond is formed when 2 electrons are transferred amongst each other.
2) Nonpolar Covalent bonds. A Nonpolar Covalent bond is formed when electrons are shared equally.
3) Polar Covalent Bonds. A Polar Covalent bond is formed when electrons are shared unequally.
Electrostatic Force
An electrostatic force exists between charged particles because of attraction or repulsion. Operates equally with each direction getting equal amounts of energy. Charged particles are put into crystal latices.
Basic Electrostatic Relationships:
1) Opposite charges attract each other.
2) Similar charges reject each other.
3) The longer the distance apart from 2 charged particles, the smaller the attracting force is between them.
4) The stronger the force of attraction is dependent on the charge of the particle.
Metals usually lose valence electrons to non-metals, while non-metals gain the non-metals. This is an example of electrons being transferred. Once metals lose electrons they become positively charged ions or Cations. Once non-metals gain electrons they become negatively-charged ions or Anions. They are very strong with high melting points, its take massive amounts of energy to break them apart.
Electronegativity
The value of the tendency of an atom to take away electrons from near by atoms. Metals tend to have low electronegativity values in comparison Non-metals have higher values. The scale that is applied to measure electronegativity is the Pauling Scale. This scales goes from Os & Fr which is 0.7 on the scale to 4.0 which is Fluorine. Atoms with high values of Electronegativity will actively attract their own electrons and electrons from near by atoms. Ionization Energy also part takes in this.
Calculating Electronegativity Difference
The simple formula is below. In caps.
ENEGRY DIFFERENCE= {ENERGY 1 - ENERGY 2}
Non Polar Covalent Bonding
Covalent bonds like Ionic bonds are strong and need large amounts of energy to break them apart.Non polar covalent bonding has equal amounts of energy spread apart. It is constructed when two atoms don't have completed shells. They share one or more electron trying to satisfy the Octet rule. The electrons at the same time are attracted to the nucleus of each atom. Non-metals will not let go of their own electrons. Single molecules that contain intramolecular covalent bonds are attached together with intermolecular forces.
Polar Covalent Bonding
Molecules that have electronegativity differences between .5-1.8 are thought to be covalent. But without equal sharing of electrons. This is called a Polar Covalent bond. An atom with a greater electronegativity will pull the electron toward its self and the electron will be closer to the atom with a higher electronegativity.
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