Ionic Compounds: much higher melting points and boiling points. Usually solids at room temperature. Most have at least some solubility in water and are insoluble in organic solvents. They ionize in water to form electrolytes which will conduct electric current through their solutions.
Covalently bonded compounds: low melting points and boiling points. Usually liquids or gases at room temperature. Some have limited solubility in water but are usually more soluble in organic solvents. Because they do not ionize in water their solutions are not electrically conductive.
Ionic compounds have high boiling n melting points,cuz of strong forces of attraction between their molecules.Covalent compounds have low BP n MP as their atoms n molecules are not bound with electrostatic forces of attraction.
Ionic compounds are water soluble n generally don't dissolve in organic solvents.They ionise in water 2 conduct electricity in the molten or fused state.
Covalent compounds don't dissolve in water,but are soluble in organic solvents like alchohol,ether,etc.Due 2 absense of ions in their structure,they don't conduct electricity in any state.