Sex and marital specialists can be just as helpful when it comes to loss of libido, so get over your resistance to asking for directions, and call one. Check with your doctor or urologistto rule out any medical conditions that may be playing a part.
Carbon is least electronegative so its attraction for electrons will be least so it will have a greater positive charge and alternatively fluorine will have a greater negative charge, so F-C bond is most polar. In F-N ,nitrogen will have lesser positive charge than carbon and fluorine will have a lesser negative charge as compared to in F-C and so on.
Polar molecules can easily interact with the outer face of the membrane, where the negatively charged head groups are found, but they have difficulty passing through its hydrophobic core. Water molecules, for instance, cannot cross the membrane rapidly (although thanks to their small size and lack of a full charge, they can cross at a slow rate).