1. Chemical Classification: Composition :Organic Chemicals / Hydrocarbons Inorganic Chemicals : Elements Salts Organometallics Use:PesiticidesSolvents HerbicidesDyes Flame retardantsagro-chemicals

2. Nomenclature Common name : Dioxin Compositional Formula : C 12 O 2 H 4 C l4 Structural Formula : Systematic Name Chemical Abstract Serial number : CAS number

3. How do you know in what physical shape the chemical is? PhasesProperties SolidMelting Point LiquidBoiling Point vapour (gas phase)Dissociation Constant dissolvedSolubility dissociated speciation

4. Expressing the Quantity of a chemical substance Solids: Units: grams, moles moles = grams/molecular weight How do you find the molecular weight? : Periodic Table

5. e.g. 100 gram kitchen salt, how many moles of salt do I have? Na: 23 + Cl: 35.5 = NaCl = 58.5 moles = 100/58.5 = 1.71 moles 1 mole of NaCl = 58.5 gram

6. Liquids: Units: liters e.g. alcohol : 1 liter To convert from liters to grams or moles : Density (kg/L) e.g. Density of Alcohol = 0.82 kg/L

7. Gases: pressure Units of pressure : N/m 2 = Pa 1 Atm = 101325 Pa 1 Torr = 1 mm hg = 133 Pa

8. 1 L Container with Cl2 gas at a pressure of 100 mm Hg and a temperature of 25 o C How many moles and grams of Cl2 do I have in that container? p.V = n.R.T p = Conc. R.T R = 8.314 J/mol/K T = 273 + 25 = 298 p = 100 mm * 133 = 13300 Pa Conc = 13300/2478 = 5.36 mol/m3 1L container = 0.001 m3 = 5.36 mmol = 5.36 *10 -3 * 71 = 0.38 gram

9. In solution: Concentrations Molarity M grams/liter ppm, ppb, ppt etc. Environmental Literature: ppth = 1 mg/mL = 1 g/L ppm = 1  g/mL = 1 mg/L ppb = 1 ng/mL = 1  g/L ppt = 1 pg/mL = 1 ng/L

10. Environmentally Relevant Chemical Properties  Solubility  Vapour pressure  Henry Law Constant  Dimensionless Air-water partition coefficient  Octanol-Water Partition Coefficient  Octanol-Air Partition Coefficient  Organic Carbon - Water Partition Coefficient  Sediment-Water Partition Coefficient

11. K sw = ------- CsCs CwCw K OC = ------- C OC CwCw Kow Koc K OC = 0.41.K ow Sediment-Water Partition coefficient Units: L/kg dry sediments Units: L/kg organic carbon Units of 0.41 are L/kg organic carbon Organic Carbon-Water Partition coefficient C S : Concentration in sediment (g/kg dry) ; C OC : Concentration in organic carbon (g/kg) C W : Concentration in water (g/L) ; K OW : Ocatnol-Water Partition Coefficient

12. K sw = ------- CSCS CWCW K OC = ------- C OC CwCw Kow Koc K oc = 0.41.K ow Sediment-Water Partition coefficient K SW (L/kg dry sediment) =  OC.K OC = 0.41.K ow Organic Carbon-Water Partition coefficient K OC (L/kg Organic carbon) C S : Concentration in sediment (g/kg dry) C OC : Concentration in organic carbon (g/kg) C W : Concentration in water (g/L) K OW : Ocatnol-Water Partition Coefficient

13. Persistence Rate Constant Half-life Residence time Residence Time = 1/rate constant Half-Life time = 0.693/rate constant Half-life = 0.693*Residence Time

16. LC50 (Lethal Concentration): Definition Is the concentration (in water, air) which when administered to a number of individuals of a certain species of organisms over a specified period of time causes death to 50% of the individuals included in the test.