5.4 Properties of ionic and covalent compound
Ionic compound
>> Exist as solid at room temperature
>> High melting and boiling point (usually > 300oC)
>> Conduct electricity in aqueous solution or molten state
>> Soluble in water but insoluble in organic solvents.
Covalent compound
>> Exist as solid, liquid and gas
>> Low melting point and boiling point
>> Do not conduct electricity at any state
>> Dissolve in organic solvent but do not dissolve in water
Electrical conductivity
>> In solid state, ions do not move freely
>> Hence, ionic compound does not conduct electricity in solid state
>> In aquoes or molten state, ions are free to move
>> Hence, the compound can conduct electricity
>> A covalent compound consist of neutral molecules
>> Hence, covalent compounds do not conduct electricity in any state
Melting and boiling points
>> Ionic compounds are held together by strong electrostatic forces.
>> More heat energy is needed to overcome the strong forces
>> That is why ionic compound have high melting point and boiling point
>> They are non-volatile solids at room temperature
>> Covalent compounds are held together by weak intermolecular forces
>> Less heat energy is needed to overcome the weak forces
>> That is why covalent compounds have low melting point and boiling. Hence, they usually exists as volatile liquids at room temperature
Uses of covalent compounds as solvents
>> Many covalent compounds such as alcohol, acetone, ether and hexane are used as solvents.
>> These compoounds are good solvents with high volatility.
>> They are widely used in various fields in our daily lives.
Ionic compound
>> Exist as solid at room temperature
>> High melting and boiling point (usually > 300oC)
>> Conduct electricity in aqueous solution or molten state
>> Soluble in water but insoluble in organic solvents.
Covalent compound
>> Exist as solid, liquid and gas
>> Low melting point and boiling point
>> Do not conduct electricity at any state
>> Dissolve in organic solvent but do not dissolve in water
Electrical conductivity
>> In solid state, ions do not move freely
>> Hence, ionic compound does not conduct electricity in solid state
>> In aquoes or molten state, ions are free to move
>> Hence, the compound can conduct electricity
>> A covalent compound consist of neutral molecules
>> Hence, covalent compounds do not conduct electricity in any state
Melting and boiling points
>> Ionic compounds are held together by strong electrostatic forces.
>> More heat energy is needed to overcome the strong forces
>> That is why ionic compound have high melting point and boiling point
>> They are non-volatile solids at room temperature
>> Covalent compounds are held together by weak intermolecular forces
>> Less heat energy is needed to overcome the weak forces
>> That is why covalent compounds have low melting point and boiling. Hence, they usually exists as volatile liquids at room temperature
Uses of covalent compounds as solvents
>> Many covalent compounds such as alcohol, acetone, ether and hexane are used as solvents.
>> These compoounds are good solvents with high volatility.
>> They are widely used in various fields in our daily lives.