[orgo814]

I'm dealing with a question that states in it's answer that a charged species will have trouble diffusing across a hydrophobic membrane. However, I am unclear as to WHY a charged species prefers aqueous phase over lipid phase. I get that interactions are weaker but what does charge have to do with aqueous preference.

Thanks for any help

[Corribus]

What is better able to stabilize a free charge, a polar or nonpolar environment? Think about the thermodynamics.

[orgo814]

I'm not exactly sure with the thermodynamic aspect. I know that if you have polar molecules surrounding a charged species it may form bonds to the H ions stabilizing it more..

[Babcock_Hall]

There are very few H⁺ ions at neutral pH; therefore, I don't know what you mean.  Negatively charged species will be attracted to the partial positive charges of H atoms within a water molecule, and positively charged species will be attracted to the partial negative charge on the oxygen atoms with a water molecule.  This is the intermolecular force known as ion-dipole attraction.