chem review pt1

• Benzene


  Aromatic group of strangely bonded<|>A ring structure<|>C & H₂ in
• Benzene formula


  C₆H₆
• Phenyl group


  The group attached to benzene
• Where benzene is found

  • Glues, adhesives, paint strippen, cleaning products, pollutants
• Benzene is carcinogenic - cancer causing
• PAHs (Polycyclic Aromatic Hydrocarbons)

  2 or more fused benzene rings<|>Bioaccumulate
• Where PAHs are found


  • Tabacco smoke, smoke from wood burning stoves, Some foods
• PAHs are Persistent Organic Pollutants (POPs) that bioaccumulate
• Carboxylic Acids


  • COOH
• Halogenated Hydrocarbons


  Organic molecules where at least one hydrogen atom has been replaced by a halogen
• Steps to name halogenated hydrocarbons

  1. Name the parent chain (longest chain of carbons)

  2. Find the halogen atoms

  3. Determine the prefix (-F, -Cl, -Br, -I)

  4. Communicate where and how many of each halogen atom appears on parent chain

  5. If more than one halogen is present, list them in alphabetical order
• LD50


  The Lethal dose of a substance, when given all at once that kills half of the population tested within a specified time
• If 200 1kg rats were given 130mg of caffeine, about 50% would die
• If 80 0.5kg rats were given 12 mg of nicotine, about 50% would die
• Bioaccumulation


  Contaminant levels increase over time in an organism
• Biomagnification


  Contaminant levels increase up the food chain
• Biological Oxygen Demand (BOD)


  The measure of the amount of oxygen used up by microorganisms (like algae) as they decompose waste
• High BOD = high amount of organic waste or sewage in water
• Things that increase BOD: Organic waste, Sewage, Warm temp, Nitrates and phosphates (fertilizer)
• Ranking water samples from lowest to highest BOD

  1. Sample C

  2. Sample B

  3. Sample A
• Pollutant types


  • Organic Matter
  • Heavy Metals
  • Dioxins & Furans
  • Pesticides (DDT)
• Organic Matter


  Animal waste, decaying plants that can deplete oxygen as it decomposes, harming aquatic life (algal blooms)
• Heavy Metals


  High atomic weight compounds like lead, mercury, highly toxic byproduct of industrial processes
• Dioxins & Furans


  Persistent environmental pollutants that are carcinogenic and bioaccumulate
• Pesticides (DDT)


  Carcinogenic or bioaccumulate