Generally polar compounds are soluble in polar solvents and non-polar compounds are soluble in non-polar solvents. Water is polar solvent and most of the organic solvents are non-polar. So mostly ionic compounds are soluble in water. Solution Generally polar compounds are soluble in polar solvents and non-polar compounds are soluble in non-polar solvents. Water is polar solvent and most of the organic solvents are non-polar. So mostly ionic compounds are soluble in water..