Many reactions involve a change in hybridization of one or more atoms in the startingmaterial. In each reaction, identify the atoms in the organic starting material that changehybridization and indicate the change. We examine these reactions in more detail later inthe course.
CHEM 111 Week 2 2-8-2016 MATTER: 1.Pure Substance -one type of atom or molecule a. Element - all one type of atom (atoms or molecules) b. Compounds - 2 or more elements in same proportion ( molecules, ionic compounds) 2. Mixture - 2 or more different things - separate them by physical property a. Homogeneous - composition doesn’t vary = solution b. Heterogenous - regions of varying composition Matter Composition (laws): - Mass Conservation: matter changes forms, not lost or gained - Definite Proportions: substance always has same composition by mass - Multiple Proportion: when 2 elements form 2 compounds, the mass of 1 element that combines with fixed mass of the other is ratio of small whole numbers 1)Dalton’s Atomic Theory: - Elements combine in simple whole number ratios to form compounds - In chemical reaction, atoms combine in new ways, but atoms remain the same 2)Rutherford : - expected, bullets to go through gold foil - reality, one hit the nucleous and bounced back Atoms: 3 subatomic particles - electrons: distributed as a cloud - protons: in the nucleus - neutrons: in the nucleus ****Protons = identity,,,electrons= personality - isotopes: same amount of protons and electrons, different amount of neutrons - elements on the periodic table isotopes of elements of average atomic weight/mass 2-12-20
