Transcript Chemistry
Chemistry, Water and pH Atom Structure Matter Mass Space Made up of atoms Protons Neutrons Electrons Definitions Element – a substance that cannot be reduced to a simpler substance Molecule – two are more atoms together Compound – two are more elements together Periodic Table Atom Structure Atomic number Mass number Atomic weight Isotopes Same element with different numbers of Neutrons Isotopes Radiometric Dating Tracers Chernobyl April 26 1986 extensive parts of the western Soviet Union, Eastern Europe, Western Europe, Northern Europe, and eastern North America Nearly thirty to forty times more fallout was released than had been by the atomic bombings of Hiroshima and Nagasaki Direct Deaths: 56 Three Mile Island March 28 1979 partial core meltdown in Unit 2 of the nuclear power plant release of a significant amount of radioactivity, an estimated 43,000 curies of radioactive krypton (1.59 PBq), but under 20 curies (740 GBq) of the particularly hazardous iodine-131, to the environment. no deaths or injuries Hershey Fukushima Daiichi March 11 2011 No immediate deaths due to radiation A few of the plant's workers were severely injured or killed by the disaster conditions at least six workers have exceeded lifetime legal limits for radiation and more than 300 have received significant radiation doses. Predicted future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged from none to 100. Microwaves Energy Levels Electron Shells “Happy Atoms” Bonding Covalent Bonding Nonpolar Polar Ionic Bonding Hydrogen Bonding Van der Waals Interactions Hydrophobic Interactions Nonpolar Covalent Bonds Polar Covalent Bonds What is an Ion? Cation A positive charged ion Anion A negatively charged ion Ionic Bonds Hydrogen Bonds Van der Waals The weak bonds that exist between molecules but are masked by other stronger bonds. They are evident only in symmetrical molecules or at very low temperatures. Hydrophobic Interactions Hydrophobic Hydrophilic Water Water Structure Polar Covalent Bonds Hydrogen Bonds Water Properties Adhesion Cohesion Surface Tension Water Properties Surface Tension – Basilisk (Jesus) Lizard Water Properties High Specific Heat Water Properties High Specific Heat Water Properties High Heat of Vaporization Water Properties Expands when freezing Water Properties Universal Solvent Solutions Solute + Solvent = Solution pH Scale Acid – donates H+ Base – accepts H+ Richter Scale Acid Precipitation Acid Precipitation Acid Precipitation Buffers