Ionic bonding

Term 2

Ionic bonding results in crystalline solids. In a crystal of sodium chloride each sodium ion is surrounded by sis chlorine iond and each chlorine ion by six sodium ions. This is called 6,6 coordination. A repeating cubical structure

Sodium is small whereas ionic is big

Back is an ionic compound with a crystalline lattice structure. It has 6,6 coordination structure which means each na+ ion is surrounded by 6 CI- ions and each CI- ion is surrounded by 6 NA+ ions

Physical properties of ionic compound

1. high melting and boiling point - during to strong electrostatic forces between ions, a large amount of energy is required to break these bonds

2. Brittleness- ionic compounds are hard but brittle example chalk because when force is applied the lattice structure shifts causing like-charged ions to repel each other and break the crystal apart

3. solubility in water - many ionic compounds dissolve in water because water molecules is surround and seperate the ions to their polarity but isn’t an organic substances

4. Electrical conductivity - ionic bonds don’t conduct electricity in a solid form but conduct when dissolved in water or melted as the ions are free to move and carry charge.

5. Crystal lattice structure - ionic compounds form a regular repeating pattern of ions called a crystal lattice which contributes to a stability and strength.

6. Density and hardness- ionic compounds tend to have high density and hardness due to their closely packed lattice structure.

Formula of ionic compounds

Mon atomic ion- consist of one atom only. Eg Cl-, Na+, CA2+, K+, Al3+, o2-

Poly atomic ion- consist of two or more atoms. Example OH-

Convalent bonding involves the sharing of electrons. This occurs because nonmentals only. Atoms may be the same type or different type.

Convalent bonding gives rise to molecules

Two or three atoms form a molecuke