Why is propanamine soluble in water but not heptanamine?

Propanamine is soluble in water due to its shorter carbon chain and the presence of an amino group that can form hydrogen bonds with water molecules. In contrast, heptanamine has a longer hydrophobic carbon chain, which reduces its overall polarity and ability to interact with water, making it less soluble. The balance between hydrophilic and hydrophobic regions in these molecules significantly affects their solubility in water.