Answer to Question #249527 in Organic Chemistry for Trac

Question

2. 1-butanamine and N-methyl-1-butanamine are soluble in water, whereas N,N-dimethylbutanamine is not soluble. Describe why the molecules have different solubilities, indicating on the structural formulas above potential site for H-bonding with water.

Answer 1

The solubility of a given solute in a given solvent typically depends on temperature. For many solids dissolved in liquid water, solubility tends to correspond with increasing temperature. As water molecules heat up, they vibrate more quickly and are better able to interact with and break apart the solute.

Hydrogen bonding does not directly affect the structure of a single water molecule. ... When water molecules interact, the hydrogen bonds pull the molecules together giving water and ice distinct properties. Hydrogen bonding is responsible for surface tension, and the crystalline structure of ice.