Ethyl 4-aminobenzoate is partially soluble in water. Generally, organic compounds are insoluble in water, due to their hydrophobic nature. In ethyl 4-aminobenzoate, there is the large, nonpolar benzene ring and the nonpolar ethyl ester functionality, which tend to make this compound insoluble in water. However, there is also an -NH2 group, which readily forms hydrogen bonds with water, favoring solubility. Very polar groups such as amino groups (-NH2) and carboxylic acid groups (-CO2H) tend to make compounds water soluble. As a rule of thumb, each polar group can balance out the insoluble nature of about 5 carbons. Ethyl 4- aminobenzoate has more than 5 carbons, so the one amino group is not enough to render the molecule soluble. However, it will dissolve a little bit in water, thus it is partially soluble. Solution Ethyl 4-aminobenzoate is partially soluble in water. Generally, organic compounds are insoluble in water, due to their hydrophobic nature. In ethyl 4-aminobenzoate, there is the large, nonpolar benzene ring and the nonpolar ethyl ester functionality, which tend to make this compound insoluble in water. However, there is also an -NH2 group, which readily forms hydrogen bonds with water, favoring solubility. Very polar groups such as amino groups (-NH2) and carboxylic acid groups (-CO2H) tend to make compounds water soluble. As a rule of thumb, each polar group can balance out the insoluble nature of about 5 carbons. Ethyl 4- aminobenzoate has more than 5 carbons, so the one amino group is not enough to render the molecule soluble. However, it will dissolve a little bit in water, thus it is partially soluble..