Chemical Bonding

NOBLE GASES

Noble gases are unreactive or stable element. Each element of noble gases has full 8 electron (octet configuration) in the outer shell with exception He. Element of He has 2 electron in the outer shell that usally called duplet configuration. The atom of noble gas, they do not combined with the other element

All element of atom besides noble gases want to be like noble gases. Because they want to be stable and unreactive element.

How do the Atom Metal and Non-Metal achieve the noble gas structure ?

Atom of noble gas has 8 electron in the outer shell. Atom metal and the other non mental try to achieve the arrangement of electron in outer shell like a noble gases.

Atom Metal reach noble gas by losing electron and the atom of metal become positive ion (Cation)
Atom non Metal reach noble gas by gaining electron and the atom of non metal become negative ion (Anion)
Atom non-metal and non metal share valence electrons

IONS

Ion are the atom or the group two or more of atom that has charge by lossing or gaining electrons. They will forming positive charge and negative charge.

Atom Metal form positive charge ions by losing electron

Atom non-metal form negative ions by gaining electrons

IONIC BONDING

Ionc Bonding is when metal react or bonded with non-metal to form ionic compound.

The appositely charge between positive metal ion and negative non metal ion are held together and attract each other by electrostatic force.

Example Ionic Bonding : NaCl, NaF, BaCl

Chemical Formula of Ionic Compound

all the positive charge must equal all the negative charged in an ionic compound

what is the chemical formula of Aluminium Sulfate ?

Structure of Ionic Compound

Ionic compound from giant ionic structure for example sodium chloride. The sodium ions and chloride ion are very strongly attracted to one another. There are millions of sodium and chloride ions arranged in orderly manners.

Physical properties of Ionic Compound

1. Non- volatile

2. High melting and boiling temperature

3. Soluble in water but unsoluble in organic solvent

4. Good electrical conductor in the molten state or aqueous solution but not in solid state

Covalent Bonding

Covalent Bond is when atom non metal bonded together with another atom non metal by sharing valence electrons. Whean atom combined they are forming molecules.

Molecules is a group two or more atoms held together by covalent bond

Molecules will classify become 2 :

1. Molecules of Element made from two or more kind types of atom bonded together by covalent bond Example : Hydogen molecules

Two atom hydrogen share 1 pair of electrons so that each atom has two electrons. The sharing of two electrons form a single covalen bond

2. Molecules of Compound made from two or more different types of atoms linked together by covalent bonding Example : H2O. CH4 and CO2

Structure of Covalent Bond

1. Simple Molecular structure. Example : H2O. CH4 and CO2

Properties of Simple Molecular Covalent Bond

1. HIgh volatility

2. Low melting and boiling temperature

3. Insoluble in water but soluble in organic solvent

4. Poor conductor of electricity

2. Giant Molecular Structure

A. Diamond : each atom carbon joined to four other carbon atoms by strong covalent bond

Properties of Diamod :

1. Hard and solid

2. Very high melting and boiling temperature

3. Poor conductor of electricity

Uses of Diamond : As gemstones, As tips of cutting, Grinding and polishing tool

B. Graphite : each atom carbon joined to three other carbon atoms by strong covalent bond

Properties of Graphite :

1. Solid and slippery

2. Very high melting and boiling temperature

3. Good conductor of electricity

Uses of graphite : As lead a pencil, as a lubricant, as inert electrodes

C. Silicon (IV) Oxide : each atom of silicon bonded with four other oxygen atom and each

atom of oxygen bonded with two silicon atom

Properties of Silicon (IV) Oxide :

1. Its Hard

2. High melting and boiling temperature

3. Poor conductor of Electricity

Uses of Silicon (IV) Oxide : production of ceramic, glass and cements.

Metallic Bonding

Metal atom are held strongly to each other by metallic bonding. In the metal lattice , the atom lose their valence electrons and become positively charge. The valence electron no longer belong to any metal ato are said to be delocalised. They move freely between the metal ion like a cloud of negative charged. Hence, the lattice structure is described as a lattice of positive ion surrounded by a sea of mobile electrons. Metallic bond as the force of attraction between positive metal ion and the sea of delocalised electrons