BCH210H1 Lecture Notes - Chemical Polarity, Hydrogen Bond, Electronegativity

• School: UTSG
• Department: Biochemistry
• Course: BCH210H1
• Professor: Stavroula Andreopoulos

Document Summary

Lecture 1 text notes non covalent interactions. Hydrogen bonds ionic attractions van der waals forces. Weak chemical forces/noncovalent bonds intra/intermolecular attractions between atoms typically range 4-30 kj/mol. Not strong enough to bind free atoms together interactions constantly forming and breaking. Between repulsive and attractive domain, there is a van der waals contact distance the interatomic distance between two atoms for the lowest energy sum of their van der waals radii. Ionic interactions result of attractive forces between oppositely charged structures (negative carboxyl and positive amine groups) strength 20 kj/mol, distance 0. 25 nm strength depends on relative polarity of interacting charged species electrical charge radially distributed interactions lack directionality. High degree of structural specificity electrostatic interactions can involve ions, permanent dipoles, or induced dipoles some ionic interactions are also hydrogen bonds. Hydrophobic interactions result from the tendency of water to exclude nonpolar groups or molecules arise because water molecules prefer strong interactions with each other compared to nonpolar molecules.