Ionic bonds result from the transfer of electrons from metal atoms to non-metal atoms, forming positive and negative ions. The electrical forces between these oppositely charged ions produce strong ionic bonds.
This kind of bonding only applies to non-metal and metal.
An example of ionic bonding:
This is a dot and cross diagram to illustrate the transferring of electrons.
This is a very simple topic, the only way to grasp the topic is to understand how it works totally.
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Chapter 2.2 Covalent Bonding
A covalent bond is formed by the sharing of a pair of electrons between 2 atoms. Each atom contributes one electron to the bond.
Covalent bonds are formed between atoms of non-metals.
Single covalent bond- 1 pair of electrons shared between two atoms
Double covalent bond- 2 pair of electrons shared between two atoms
Triple covalent bond- 3 pair of electrons shared between two atoms
This diagram above shows how covalent bonds are formed.
Valency:
The number of electrons an atom uses to form bods is called its valency.
Extra:
Bond breaking is endothermic because it requires energy.
Bond making is exothermic helps the atom become more stable thus giving out energy.
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1) High Density
1) Attraction between '+' and '-' ions.
1) Hard
1) Strong covalent bonds between atoms but weak intermolecular forces between separate molecules.
1) Substances with Giant Structures are often hard with high melting and boiling points.
Chapter 2.3 Structure and Properties
There are 4 Types of structure and they are.....
1) Giant Metallic
2) Giant Covalent
3) Giant ionic
4) Simple molecular
According to the 4 types of structure, the particles in it are:
1) Atoms (Giant metallic)
2) Very large molecule containing thousands thousands of atoms
3) Ions
4) Small molecules containing a few atoms (Simple molecular)
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PROPERTIES OF METALS:
1) High Density
2) High Melting & Boiling point.
3) Good Conductivity
4) Malleability
PROPERTIES OF Giant Ionic Structure:
1) Attraction between '+' and '-' ions.
PROPERTIES OF Giant Covalent Structure:
1) Hard
2) High melting point
3) Does not conduct electricity
PROPERTIES OF Simple molecular substances:
1) Strong covalent bonds between atoms but weak intermolecular forces between separate molecules.
The weak intermolecular forces are called Van der Waals Forces.
2) Soft
3) Low melting and boiling point
4) Does not conduct electricity
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Key Points for the 4 types of structure:
1) Substances with Giant Structures are often hard with high melting and boiling points.
2) Substances with Simple Molecular structures are usually soft with low melting points and boling points.
3) There are 3 types of strong force between particles in giant structures:
a) Metallic Bonds (Metal and Metal)
b) Covalent Bonds (Non-metal and Non-metal)
c) Ionic Bonds (Metal and Non-metal)
4) Simple molecular substances have relatively weak forces between separate molecules (Van der Waals forces)
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