Chemistry

Chemistry class is going to squeeze me out this semester. There are one assessment quiz which will determine the amount of homework i'm gonna get for that week,and an examination on every friday. On one hand, it is a good thing, I will learn the concepts well enough to actually make a good use of it later. Maybe, hopefully, it will make me like chemistry a little more. But on the other hand, it's going to be loads of work including reading, online homework assignments(i'm sure there will be,for i'm not too sure if i will do well enough on those assessment quizzes to not get assigned any homework) and solving lots of of problems to be able to do well on the exams. But the important thing is that the teacher is not boring. Actually he deserves more than being rated as "not-boring". He knows what he's doing, and at least he doesn't stray off into non related topics and self-experience-talk, gosh, one teacher that i had used to just go on and on about himself. The textbook we're utilizing is by Kotz "Chemical Reactivity". Skipping the 11th chapter "Gas", we're now studying the 12th chapter " Intermolecular Forces and Liquids". There are 4 types of IMF's 1. ion-dipole force
2.dipole-dipole force
3.hydrogen bonding [Strongest IMF]
4.London force aka dispersion F [weakest IMF ; all molecules have london F]
Everything here is pretty self-explanatory. He emphasized at the beginning of the lecture that "covalent molecules are island of atoms with covalent bonds connecting them, and ionic solid is defined as extended lattice of ions with coulombic forces between them; therefore, there's not such thing as a molecule of NaCl".
Enthalpy is denoted by deltaH(hydration) and it is the sum of the internal energy in the system. When an ion dissolves in water it gives off energy. Also enthalpy depends on the distance between water molecules and ion. So bigger the atom is, less the energy given off.
Hydrogen bonds need 1.acidic H (N,F,O,Cl,I,Br)
2.basic lone pair (N,O,F)
Amazing substance WATER!!!

Also, there are extensive h-bonds in human body. All the nucleic acids in our body( DNAs and RNAs)can't exist without hydrogen bonding. DNA strand is made up of two sugar-phosphate chains are connected to each other with their bases( Adenine, Guanine, Thymine, Cytosine, Uracil in RNAs) through this essential bond.Also, all the polymers in body proteins (alpha helix beta sheets and all that...) are connected through h-bond.
London force forms when there are two non polar molecules get connected to each other with the help of induced dipole. So where is this induced dipole coming from? At any given infinitesimally small moment, electrons that are moving randomly cluster at one side of the atom, which makes it slightly charged negatively/positively on the other side; consequently, there's an attraction between the atoms.
One statement that he clearly said was " IMF is not a chemical bond" .Pretty obvious,isn't it? Righttt??

Low vapor pressure=few molecules in gas phase = high bp
High vapor pressure= lots of molecules in gas phase =low bp

Clausius Clapyran Equation (he says don't laugh at the name, but everyone did right after he said that,,haha!)

This equation helps us calculate the vapor pressure at one given time if we know the enthalpy of vaporization and vap.press at another given time.