What is combustion analysis What is it used for

• organic chemistry - chemistry of carbon-containing compounds organic chemistry is about structure (how atoms are bonded) and reactivity (how bonding • changes) • chemical bond —joining of atoms in stable arrangement —energy of electrons lowered b/c electrons feel charge of 2 nuclei —ionic bonding A. transfer of electrons B. forms salt crystal lattice (not a molecule), non-directional bonding —covalent bonding A. sharing of electrons B. forms discrete bonds, directional bonding —discrete bonding may result in multiple possible structures called isomers —different molecules with the same molecular formula but different atom connectivity are constitutional isomers how many covalent bonds does an atom make in a neutral molecule • —atoms with 1-4 valence e-: # bonds = # valence e- —atoms with 5 or more valence e-: # bonds = 8 - # valence e- —elements to remember A. carbon = 4 bonds B. nitrogen = 3 bonds C. oxygen = 2 bonds D. hydrogen = 1 bond E. halogens (F, Cl, Br, I) = 1 bond —important rule: 2nd period elements (1st row of p-block) never exceed 8 e- in valence shell—>never more than 4 bonds • formal charge is the charge assigned to an atom assuming electrons are shared equally —difference between what an atom should have when neutral and what it actually has —formal charge = # valence electrons - # electrons surrounding atom • electronegativity is a measu