The second general category of hydrocarbons is aromatics. The simplest aromatic ring is benzene:

1. Alkanes are hydrocarbon compounds that contain only single bonds between carbon atoms. Alkanes are also referred to as saturated compounds.

2. Many organic compounds have both a systematic and a common name. This is due in part to the way the science of organic chemistry developed.

3. If a double bond has two identical groups, the prefixes “cis-” and “trans-” are used. (Cis- denotes two identical groups on the same side of the molecule. Trans-is used if they are on opposite sides.)

4. The second general category of hydrocarbons is aromatics. The simplest aromatic ring is benzene:

5. Nomenclature of substituted benzenes is divided into two categories. For mono-substitute compounds, benzene is the base name and the group is designated as a prefix.

6. FIGURE 3-1 Distribution of two different organic chemicals between a soil phase and a water phase.

7. FIGURE 3-2 Relationship between organic carbon content of solid materials to soil-water partition coefficient for selected benzene compounds.

8. FIGURE 3-3 Relationship between the bioconcentration factor and K ow.

9. FIGURE 3-4 A system that may undergo a quasi-equilibrium process.

10. FIGURE 3-5 A system that may be considered to undergo a reversible process.

11. FIGURE 3-6 First- and second-order plots for Example 3-20.

12. FIGURE 3-7 Response to step and impulse inputs.

13. FIGURE 3-8 Recycle reactor.

14. Esters have the general formula RCO2R. An ester is formed by reacting a carboxylic acid with an alcohol. To name an ester, the name of the alkyl radical (R) from the alcohol comes first, followed by the name of the carboxylate ion or salt. The carboxylate ion has the general formula R–CO 2 .

15. Phthalate esters contain the phthalate ion and any alkyl groups.

16. A somewhat different class of organic compounds are ketones.

17. Volatile organic compounds (VOCs) have a high vapor ressure that allows them to evaporate quickly. In general, they are relatively low molecular weight compounds.

18. acid extractables are aromatic alcohols or phenols.

19. Particularly good against the boll weevil, the cotton aphid and the locust.

20. Good mosquito repellent

21. Common moth repellent

22. Methoxy analog of DDT; can be used in dairies without imparting toxicity or off-taste to milk

23. Fairly low toxicity to mammals

24. Moderate toxicity to mammals

25. Moderate toxicity to mammals

26. Moderate toxicity to mammals

27. Fairly high toxicity to mammals

28. High toxicity to mammals

29. Heteroatoms such as nitrogen, oxygen, and sulfur can be substituted into PAHs. Some of these compounds such as carbazole are characteristic of manufactured gas plant (MGP) wastes. Dibenzofuran and dibenzo-p -dioxin are unwanted combustion by-products.

30. EXAMPLE 3-2. STRUCTURAL FORMULAS.

31. When more than two groups are present, numbers must be used to indicate the positions. The ring is numbered so the groups have the lowest possible numbers.

32. For some compounds, common names used most often are:

33. Dimethylbenzenes are given the common name xylenes.

34. When a benzene ring is itself a substituent of a larger group, it is called phenyl.

35. Polynuclear aromatic hydrocarbons (PAHs) are groups of aromatic rings containing only carbon and hydrogen. They may be considered as two or more benzene rings fused together with at least two common carbons.

36. Amines are considered organic derivatives of ammonia. They are classified as primary, secondary, or tertiary mines, by the number of attached alkyl groups.

37. A nitrosamine has the nitroso group ( .N =O), as one of the alkyl groups.